ensure sidekick library can construct appropriate urls

[MarquiseRosier]

Please always provide the GitHub issue(s) your PR is for, as well as test URLs where your change can be observed (before and after):

Fix #366

Test URLs:

• Before:
  • https://main--shredit--stericycle.aem.page/tools/sidekick/library.html?plugin=blocks&path=/tools/sidekick/blocks/post-teaser-list&index=0
• After:
  • https://bugfix-366--shredit--stericycle.aem.page/tools/sidekick/library.html?plugin=blocks&path=/tools/sidekick/blocks/post-teaser-list&index=0

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Commits

* [4e5a4e7](https://github.com/aemsites/stericycle-shared/commit/4e5a4e715d7ee54cffe29ec8107db1483b0d7ff3) :white_check_mark: (latest)

[aem-code-sync[bot]]

	Page	Scores	Audits	Google
:iphone:	/tools/sidekick/library.html?plugin=blocks&path=/tools/sidekick/blocks/post-teas er-list&index=0
:desktop_computer:	/tools/sidekick/library.html?plugin=blocks&path=/tools/sidekick/blocks/post-teas er-list&index=0