fix: add check before performing chmod on the code coverage path (#262)

* fix: add check before performing chmod on the code coverage path, as it does not exist if the package is not installed

* fix: generalise the dir not existing message more

* fix: improve guide message

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Co-authored-by: Quake <QuakeEye@users.noreply.GitHub.com>

dist/platforms/ubuntu/run_tests.sh

@@ -274,4 +274,10 @@ fi
 # Add read permissions for everyone to all artifacts
 chmod -R a+r "$UNITY_PROJECT_PATH"
 chmod -R a+r "$FULL_ARTIFACTS_PATH"
-chmod -R a+r "$FULL_COVERAGE_RESULTS_PATH"
+
+# Check if coverage results directory exists
+if [ -d "$FULL_COVERAGE_RESULTS_PATH" ]; then
+  chmod -R a+r "$FULL_COVERAGE_RESULTS_PATH"
+else
+  echo "Coverage results directory does not exist. If you are expecting coverage results, please make sure the Code Coverage package is installed in your unity project and that it is set up correctly."
+fi