fix: unique function names

[hallvictoria]

Description

• Refactors variables into template file to prevent duplicate code. Adding variables can now be done in one spot
  • Variables.yml holds variables that can be used in public piplines
  • Official-variables.yml holds variables that can be used in internal pipelines
• Removes -U flag when installing test sdk / extensions
  • Addresses an issue where, after installing the test version, the version specified in pyproject.toml was installed and overwrote the test version
• Refactors deferred bindings unit tests
  • Moves to 1 single file
  • Deletes the function_app module after each test to prevent caching error
  • Fixes dispatcher unit tests
• Deletes the function_app module after each test to prevent caching error

Fixes #

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