test: reduce the number of examples tests running in parallel

- `t.Parallel()` marks a test function, telling Go that it can be run
in parallel with other functions in the same package.
- `-parallel` determines "how many test functions inside a single test
package can run in parallel".

As all examples tests are using `t.Parallel()`, they all run in
parallel. This might overwhelm the kind cluster a bit. This is making
sure we run at most 6 of them at the same time.

It also removes the parents `t.Parallel()` as this is.. just weird.

Signed-off-by: Vincent Demeester <vdemeest@redhat.com>

Author: vdemeester

test/e2e-tests.sh

@@ -174,7 +174,7 @@ function run_e2e() {
   # and they cause a lot of noise in the logs, making it harder to debug integration
   # test failures.
   if [ "${RUN_YAML_TESTS}" == "true" ]; then
-    go_test_e2e -mod=readonly -tags=examples -timeout=${E2E_GO_TEST_TIMEOUT} ./test/
+    go_test_e2e -mod=readonly -parallel=6 -tags=examples -timeout=${E2E_GO_TEST_TIMEOUT} ./test/
   fi
 
   if [ "${RUN_FEATUREFLAG_TESTS}" == "true" ]; then

test/examples_test.go

@@ -203,7 +203,6 @@ func TestExamples(t *testing.T) {
 }
 
 func testYamls(t *testing.T, baseDir string, createFunc createFunc, filter pathFilter) {
-	t.Parallel()
 	for _, path := range getExamplePaths(t, baseDir, filter) {
 		path := path // capture range variable
 		testName := extractTestName(baseDir, path)