chore: Removing CI references to Nix (#3844)

Signed-off-by: James Turnbull <[email protected]>

CONTRIBUTING.md

@@ -219,13 +219,13 @@ $ curl -u "$GITHUB_USERNAME:$GITHUB_TOKEN" \
 
 We're super excited to have you interested in working on Vector! Before you start you should pick how you want to develop.
 
-For small or first-time contributions, we recommend the Docker method. If you do a lot of contributing, try adopting the Nix method! It'll be way faster and feel more smooth. Prefer to do it yourself? That's fine too!
+For small or first-time contributions, we recommend the Docker method. Prefer to do it yourself? That's fine too!
 
 #### Using a Docker or Podman environment
 
 > **Targets:** You can use this method to produce AARCH64, Arm6/7, as well as x86/64 Linux builds.
 
-Since not everyone has a full working native environment, or can use Nix, we took our Nix environment and stuffed it into a Docker (or Podman) container!
+Since not everyone has a full working native environment, we took our environment and stuffed it into a Docker (or Podman) container!
 
 This is ideal for users who want it to "Just work" and just want to start contributing. It's also what we use for our CI, so you know if it breaks we can't do anything else until we fix it. 😉
 

Makefile

@@ -44,7 +44,7 @@ export ENVIRONMENT_UPSTREAM ?= docker.pkg.github.com/timberio/vector/environment
 # Override to disable building the container, having it pull from the Github packages repo instead
 # TODO: Disable this by default. Blocked by `docker pull` from Github Packages requiring authenticated login
 export ENVIRONMENT_AUTOBUILD ?= true
-# Override this when appropriate to disable a TTY being available in commands with `ENVIRONMENT=true` (Useful for CI, but CI uses Nix!)
+# Override this when appropriate to disable a TTY being available in commands with `ENVIRONMENT=true`
 export ENVIRONMENT_TTY ?= true
 # A list of WASM modules by name
 export WASM_MODULES = $(patsubst tests/data/wasm/%/,%,$(wildcard tests/data/wasm/*/))
@@ -72,7 +72,6 @@ help:
 	@printf -- "                                      V E C T O R\n"
 	@printf -- "\n"
 	@printf -- "---------------------------------------------------------------------------------------\n"
-	@printf -- "Nix user? You can use ${FORMATTING_BEGIN_YELLOW}\`direnv allow .\`${FORMATTING_END} or ${FORMATTING_BEGIN_YELLOW}\`nix-shell --pure\`${FORMATTING_END}\n"
 	@printf -- "Want to use ${FORMATTING_BEGIN_YELLOW}\`docker\`${FORMATTING_END} or ${FORMATTING_BEGIN_YELLOW}\`podman\`${FORMATTING_END}? See ${FORMATTING_BEGIN_YELLOW}\`ENVIRONMENT=true\`${FORMATTING_END} commands. (Default ${FORMATTING_BEGIN_YELLOW}\`CONTAINER_TOOL=docker\`${FORMATTING_END})\n"
 	@printf -- "\n"
 	@awk 'BEGIN {FS = ":.*##"; printf "Usage: make ${FORMATTING_BEGIN_BLUE}<target>${FORMATTING_END}\n"} /^[a-zA-Z0-9_-]+:.*?##/ { printf "  ${FORMATTING_BEGIN_BLUE}%-46s${FORMATTING_END} %s\n", $$1, $$2 } /^##@/ { printf "\n\033[1m%s\033[0m\n", substr($$0, 5) } ' $(MAKEFILE_LIST)
@@ -871,9 +870,6 @@ verify-deb-artifact-on-ubuntu-18-04: package-deb-x86_64 ## Verify the deb packag
 verify-deb-artifact-on-ubuntu-20-04: package-deb-x86_64 ## Verify the deb package on Ubuntu 20.04
 	$(RUN) verify-deb-artifact-on-ubuntu-20-04
 
-verify-nixos:  ## Verify that Vector can be built on NixOS
-	$(RUN) verify-nixos
-
 ##@ Utility
 
 build-ci-docker-images: ## Rebuilds all Docker images used in CI