fix: skip file opened event for template watcher

[mndeveci]

Which issue(s) does this change fix?

#7058

Why is this change necessary?

When watching the template.yaml file, file opened event gets triggered indefinitely for some cases on Linux systems, which causes high CPU usage.

How does it address the issue?

We already skipping file opened event for some other file watchers for the sam sync, this PR also applies same fix to the template listener as well.

What side effects does this change have?

Since file opened event is already skipped in other places, this shouldn't have any side affects for this usage as well.

Mandatory Checklist

PRs will only be reviewed after checklist is complete

• Add input/output type hints to new functions/methods
• Write design document if needed (Do I need to write a design document?)
• Write/update unit tests
• Write/update integration tests
• Write/update functional tests if needed
• make pr passes
• make update-reproducible-reqs if dependencies were changed
• Write documentation

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.