Use standardized strings for subscription keys and endpoints to enable automated testing

[v-jaswel]

Does this introduce a breaking change?

[ ] Yes
[x ] No

Pull Request Type

What kind of change does this Pull Request introduce?

[ ] Bugfix
[ ] Feature
[ ] Code style update (formatting, local variables)
[ ] Refactoring (no functional changes, no api changes)
[ ] Documentation content changes
[ ] Other... Please describe:

How to Test

• Get the code

git clone [repo-address]
cd [repo-name]
git checkout [branch-name]
npm install

• Test the code

What to Check

Verify that the following are valid

• ...

Other Information

[ghost]

All CLA requirements met.

[v-jaswel]

Requesting review from @nitinme or @PatrickFarley. I don't seem to have permission to add reviewers in the right sidebar.