[runners-flink] Drop Flnk 1.14 and clean up code (apache#31112)

.github/actions/setup-default-test-properties/test-properties.json

@@ -13,8 +13,8 @@
     "TOX_ENV": ["Cloud", "Cython"]
   },
   "JavaTestProperties": {
-    "SUPPORTED_VERSIONS": ["8", "11", "17"],
-    "FLINK_VERSIONS": ["1.13", "1.14", "1.15"],
+    "SUPPORTED_VERSIONS": ["8", "11", "17", "21"],
+    "FLINK_VERSIONS": ["1.15", "1.16", "1.17", "1.18"],
     "SPARK_VERSIONS": ["2", "3"]
   },
   "GoTestProperties": {

gradle.properties

@@ -39,6 +39,6 @@ docker_image_default_repo_root=apache
 docker_image_default_repo_prefix=beam_
 
 # supported flink versions
-flink_versions=1.14,1.15,1.16,1.17,1.18
+flink_versions=1.15,1.16,1.17,1.18
 # supported python versions
 python_versions=3.8,3.9,3.10,3.11

learning/tour-of-beam/learning-content/java/introduction/introduction-concepts/runner-concepts/description.md

@@ -111,7 +111,7 @@ Additionally, you can read [here](https://beam.apache.org/documentation/runners/
 #### Run example
 
 ##### Portable
-1. Starting with Beam 2.18.0, pre-built Flink Job Service Docker images are available at Docker Hub: `Flink 1.10`, `Flink 1.11`, `Flink 1.12`, `Flink 1.13`, `Flink 1.14`.
+1. Starting with Beam 2.18.0, pre-built Flink Job Service Docker images are available at Docker Hub: `Flink 1.15`, `Flink 1.16`, `Flink 1.17`, `Flink 1.18`.
 2. Start the JobService endpoint: `docker run --net=host apache/beam_flink1.10_job_server:latest`
 3. Submit the pipeline to the above endpoint by using the PortableRunner, job_endpoint set to localhost:8099 (this is the default address of the JobService). Optionally set environment_type set to LOOPBACK. For example: