Align request compression config options to other SDKs

[sbiscigl]

Description of changes:

Our environment variables and configuration variables are not aligned with what other SDKs use for request compression being enabled.

aws docs for reference

Check all that applies:

• [x] Did a review by yourself.
• [x] Added proper tests to cover this PR. (If tests are not applicable, explain.)
• [x] Checked if this PR is a breaking (APIs have been changed) change.
• [x] Checked if this PR will not introduce cross-platform inconsistent behavior.
• [x] Checked if this PR would require a ReadMe/Wiki update.

Check which platforms you have built SDK on to verify the correctness of this PR.

• [x] Linux
• [x] Windows
• [ ] Android
• [x] MacOS
• [ ] IOS
• [ ] Other Platforms

By submitting this pull request, I confirm that you can use, modify, copy, and redistribute this contribution, under the terms of your choice.