Enhance/5044 tag manager amp effect

[kuasha420]

Summary

Addresses issue:

• Fix Tag Manager useExistingTagEffect to properly work in case of primary AMP #5044

Relevant technical choices

PR Author Checklist

• My code is tested and passes existing unit tests.
• My code has an appropriate set of unit tests which all pass.
• My code is backward-compatible with WordPress 4.7 and PHP 5.6.
• My code follows the WordPress coding standards.
• My code has proper inline documentation.
• I have added a QA Brief on the issue linked above.
• I have signed the Contributor License Agreement (see https://cla.developers.google.com/).

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Code Reviewer Checklist

• Run the code.
• Ensure the acceptance criteria are satisfied.
• Reassess the implementation with the IB.
• Ensure no unrelated changes are included.
• Ensure CI checks pass.
• Check Storybook where applicable.
• Ensure there is a QA Brief.

Merge Reviewer Checklist

• Ensure the PR has the correct target branch.
• Double-check that the PR is okay to be merged.
• Ensure the corresponding issue has a ZenHub release assigned.
• Add a changelog message to the issue.

[github-actions]

Size Change: +43 B (0%)

Total Size: 1.35 MB

Filename	Size	Change
./dist/assets/js/googlesitekit-modules-tagmanager-********************.js	29.8 kB	+43 B (0%)

ℹ️ View Unchanged

Filename	Size
./dist/assets/css/googlesitekit-admin-css-********************.min.css	42.4 kB
./dist/assets/css/googlesitekit-adminbar-css-********************.min.css	11.3 kB
./dist/assets/css/googlesitekit-wp-dashboard-css-********************.min.css	6.48 kB
./dist/assets/js/32-********************.js	51.9 kB
./dist/assets/js/33-********************.js	3.12 kB
./dist/assets/js/analytics-advanced-tracking-********************.js	769 B
./dist/assets/js/googlesitekit-activation-********************.js	33.4 kB
./dist/assets/js/googlesitekit-adminbar-********************.js	37.1 kB
./dist/assets/js/googlesitekit-api-********************.js	9.41 kB
./dist/assets/js/googlesitekit-base-********************.js	1.58 kB
./dist/assets/js/googlesitekit-dashboard-********************.js	55.5 kB
./dist/assets/js/googlesitekit-dashboard-details-********************.js	51.1 kB
./dist/assets/js/googlesitekit-dashboard-splash-********************.js	67 kB
./dist/assets/js/googlesitekit-data-********************.js	2.09 kB
./dist/assets/js/googlesitekit-datastore-forms-********************.js	9.04 kB
./dist/assets/js/googlesitekit-datastore-location-********************.js	2.08 kB
./dist/assets/js/googlesitekit-datastore-site-********************.js	14.7 kB
./dist/assets/js/googlesitekit-datastore-ui-********************.js	9.13 kB
./dist/assets/js/googlesitekit-datastore-user-********************.js	22.2 kB
./dist/assets/js/googlesitekit-i18n-********************.js	3.92 kB
./dist/assets/js/googlesitekit-idea-hub-notice-********************.js	4.96 kB
./dist/assets/js/googlesitekit-idea-hub-post-list-********************.js	25.9 kB
./dist/assets/js/googlesitekit-module-********************.js	47.6 kB
./dist/assets/js/googlesitekit-modules-adsense-********************.js	68 kB
./dist/assets/js/googlesitekit-modules-analytics-4-********************.js	19.2 kB
./dist/assets/js/googlesitekit-modules-analytics-********************.js	73.5 kB
./dist/assets/js/googlesitekit-modules-********************.js	17.3 kB
./dist/assets/js/googlesitekit-modules-idea-hub-********************.js	34.7 kB
./dist/assets/js/googlesitekit-modules-optimize-********************.js	19.4 kB
./dist/assets/js/googlesitekit-modules-pagespeed-insights-********************.js	18.8 kB
./dist/assets/js/googlesitekit-modules-search-console-********************.js	40.6 kB
./dist/assets/js/googlesitekit-modules-subscribe-with-google-********************.js	17.8 kB
./dist/assets/js/googlesitekit-polyfills-********************.js	380 B
./dist/assets/js/googlesitekit-settings-********************.js	51.5 kB
./dist/assets/js/googlesitekit-user-input-********************.js	47.6 kB
./dist/assets/js/googlesitekit-vendor-********************.js	318 kB
./dist/assets/js/googlesitekit-widgets-********************.js	19.5 kB
./dist/assets/js/googlesitekit-wp-dashboard-********************.js	60.5 kB
./dist/assets/js/runtime-********************.js	1.22 kB

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[asvinb]

Thanks @kuasha420 . LGTM!

[eugene-manuilov]

LGTM