[editorial] Fix log omissions in OTLP exporter env vars document (ope…

…n-telemetry#3763)

Noticed some log omissions in the OTLP exporter doc where traces and
metrics are mentioned. This change is editorial.

specification/protocol/exporter.md

@@ -13,11 +13,11 @@ This document specifies the configuration options available to the OpenTelemetry
 The following configuration options MUST be available to configure the OTLP exporter.
 Each configuration option MUST be overridable by a signal specific option.
 
-- **Endpoint (OTLP/HTTP)**: Target URL to which the exporter is going to send spans or metrics. The endpoint MUST be a valid URL with scheme (http or https) and host, MAY contain a port, SHOULD contain a path and MUST NOT contain other parts (such as query string or fragment). A scheme of https indicates a secure connection. When using `OTEL_EXPORTER_OTLP_ENDPOINT`, exporters MUST construct per-signal URLs as  [described below](#endpoint-urls-for-otlphttp). The per-signal endpoint configuration options take precedence and can be used to override this behavior (the URL is used as-is for them, without any modifications). See the [OTLP Specification][otlphttp-req] for more details.
+- **Endpoint (OTLP/HTTP)**: Target URL to which the exporter is going to send spans, metrics, or logs. The endpoint MUST be a valid URL with scheme (http or https) and host, MAY contain a port, SHOULD contain a path and MUST NOT contain other parts (such as query string or fragment). A scheme of https indicates a secure connection. When using `OTEL_EXPORTER_OTLP_ENDPOINT`, exporters MUST construct per-signal URLs as  [described below](#endpoint-urls-for-otlphttp). The per-signal endpoint configuration options take precedence and can be used to override this behavior (the URL is used as-is for them, without any modifications). See the [OTLP Specification][otlphttp-req] for more details.
   - Default:  `http://localhost:4318` [1]
   - Env vars: `OTEL_EXPORTER_OTLP_ENDPOINT` `OTEL_EXPORTER_OTLP_TRACES_ENDPOINT` `OTEL_EXPORTER_OTLP_METRICS_ENDPOINT` `OTEL_EXPORTER_OTLP_LOGS_ENDPOINT`
 
-- **Endpoint (OTLP/gRPC)**: Target to which the exporter is going to send spans or metrics. The endpoint SHOULD accept any form allowed by the underlying gRPC client implementation. Additionally, the endpoint MUST accept a URL with a scheme of either `http` or `https`. A scheme of `https` indicates a secure connection and takes precedence over the `insecure` configuration setting. A scheme of `http` indicates an insecure connection and takes precedence over the `insecure` configuration setting. If the gRPC client implementation does not support an endpoint with a scheme of `http` or `https` then the endpoint SHOULD be transformed to the most sensible format for that implementation.
+- **Endpoint (OTLP/gRPC)**: Target to which the exporter is going to send spans, metrics, or logs. The endpoint SHOULD accept any form allowed by the underlying gRPC client implementation. Additionally, the endpoint MUST accept a URL with a scheme of either `http` or `https`. A scheme of `https` indicates a secure connection and takes precedence over the `insecure` configuration setting. A scheme of `http` indicates an insecure connection and takes precedence over the `insecure` configuration setting. If the gRPC client implementation does not support an endpoint with a scheme of `http` or `https` then the endpoint SHOULD be transformed to the most sensible format for that implementation.
   - Default: `http://localhost:4317` [1]
   - Env vars: `OTEL_EXPORTER_OTLP_ENDPOINT` `OTEL_EXPORTER_OTLP_TRACES_ENDPOINT` `OTEL_EXPORTER_OTLP_METRICS_ENDPOINT` `OTEL_EXPORTER_OTLP_LOGS_ENDPOINT`
 
@@ -138,7 +138,7 @@ relative to `http://collector:4318/mycollector/`.
 
 ### Specify Protocol
 
-The `OTEL_EXPORTER_OTLP_PROTOCOL`, `OTEL_EXPORTER_OTLP_TRACES_PROTOCOL`, and `OTEL_EXPORTER_OTLP_METRICS_PROTOCOL` environment variables specify the OTLP transport protocol. Supported values:
+The `OTEL_EXPORTER_OTLP_PROTOCOL`, `OTEL_EXPORTER_OTLP_TRACES_PROTOCOL`, `OTEL_EXPORTER_OTLP_METRICS_PROTOCOL` and `OTEL_EXPORTER_OTLP_LOGS_PROTOCOL` environment variables specify the OTLP transport protocol. Supported values:
 
 - `grpc` for protobuf-encoded data using gRPC wire format over HTTP/2 connection
 - `http/protobuf` for protobuf-encoded data over HTTP connection
@@ -155,7 +155,7 @@ release).
 
 ### Specifying headers via environment variables
 
-The `OTEL_EXPORTER_OTLP_HEADERS`, `OTEL_EXPORTER_OTLP_TRACES_HEADERS`, `OTEL_EXPORTER_OTLP_METRICS_HEADERS` environment variables will contain a list of key value pairs, and these are expected to be represented in a format matching to the [W3C Correlation-Context](https://github.com/w3c/baggage/blob/master/baggage/HTTP_HEADER_FORMAT.md), except that additional semi-colon delimited metadata is not supported, i.e.: key1=value1,key2=value2. All attribute values MUST be considered strings.
+The `OTEL_EXPORTER_OTLP_HEADERS`, `OTEL_EXPORTER_OTLP_TRACES_HEADERS`, `OTEL_EXPORTER_OTLP_METRICS_HEADERS`, `OTEL_EXPORTER_OTLP_LOGS_HEADERS` environment variables will contain a list of key value pairs, and these are expected to be represented in a format matching to the [W3C Correlation-Context](https://github.com/w3c/baggage/blob/master/baggage/HTTP_HEADER_FORMAT.md), except that additional semi-colon delimited metadata is not supported, i.e.: key1=value1,key2=value2. All attribute values MUST be considered strings.
 
 ## Retry