[CI] Cleanup buildkite test report script

This patch removes the generate_test_report_buildkite script entrypoint
as we no longer need it now that buildkite has been sunsetted. Also
remove the calls in the monolithic-* scripts given they are adding
complexity for no value.

Also remove the generate-buildkite-pipeline-premerge script as it is
no longer needed.

Reviewers: tstellar, DavidSpickett, lnihlen, cmtice

Reviewed By: DavidSpickett

Pull Request: #143480

Author: boomanaiden154

.ci/generate-buildkite-pipeline-premerge

@@ -42,14 +42,9 @@ function at-exit {
 
   # If building fails there will be no results files.
   shopt -s nullglob
-  if command -v buildkite-agent 2>&1 >/dev/null
-  then
-    python3 "${MONOREPO_ROOT}"/.ci/generate_test_report_buildkite.py ":linux: Linux x64 Test Results" \
-      "linux-x64-test-results" $retcode "${BUILD_DIR}"/test-results.*.xml
-  else
-    python3 "${MONOREPO_ROOT}"/.ci/generate_test_report_github.py ":penguin: Linux x64 Test Results" \
-      $retcode "${BUILD_DIR}"/test-results.*.xml >> $GITHUB_STEP_SUMMARY
-  fi
+  
+  python3 "${MONOREPO_ROOT}"/.ci/generate_test_report_github.py ":penguin: Linux x64 Test Results" \
+    $retcode "${BUILD_DIR}"/test-results.*.xml >> $GITHUB_STEP_SUMMARY
 }
 trap at-exit EXIT
 

.ci/generate_test_report_buildkite.py

@@ -37,14 +37,9 @@ function at-exit {
 
   # If building fails there will be no results files.
   shopt -s nullglob
-  if command -v buildkite-agent 2>&1 >/dev/null
-  then
-    python "${MONOREPO_ROOT}"/.ci/generate_test_report_buildkite.py ":windows: Windows x64 Test Results" \
-      "windows-x64-test-results" $retcode "${BUILD_DIR}"/test-results.*.xml
-  else
-    python "${MONOREPO_ROOT}"/.ci/generate_test_report_github.py ":window: Windows x64 Test Results" \
-      $retcode "${BUILD_DIR}"/test-results.*.xml >> $GITHUB_STEP_SUMMARY
-  fi
+    
+  python "${MONOREPO_ROOT}"/.ci/generate_test_report_github.py ":window: Windows x64 Test Results" \
+    $retcode "${BUILD_DIR}"/test-results.*.xml >> $GITHUB_STEP_SUMMARY
 }
 trap at-exit EXIT