build: always ensure node_modules folders are not picked up in AIO (#48329)

AIO has two risk places where `node_modules` folders may exist and may
be accidentally picked up by Bazel- even though they are already added
as part of `.bazelignore` and made visible through `.gitignore`. It
doesn't hurt instructing Bazel to always ignore `node_modules` as part
of the `glob` instruction.

Co-authored-by: Joey Perrott <josephperrott@gmail.com>

PR Close #48329

aio/content/examples/examples.bzl

@@ -115,7 +115,10 @@ def docs_example(name, test = True, test_tags = [], test_exec_properties = {}, f
 
     native.filegroup(
         name = "files",
-        srcs = native.glob(["**"], exclude = ["BUILD.bazel"]),
+        srcs = native.glob(["**"], exclude = [
+            "BUILD.bazel",
+            "**/node_modules/**",  # Node modules may exist from the legacy setup.
+        ]),
     )
 
     # Generate example boilerplate

aio/tools/examples/shared/BUILD.bazel

@@ -4,6 +4,9 @@ filegroup(
     name = "shared",
     srcs = glob(
         ["**"],
-        exclude = ["BUILD.bazel"],
+        exclude = [
+            "BUILD.bazel",
+            "**/node_modules/**",  # Node modules may exist from the legacy setup.
+        ],
     ),
 )