Refactor and simplify logic in sdksCommon cmake script

[SergeyRyabinin]

Issue #, if available:
cmake logic depends on c2j file list in tools/code-generation/api-descriptions
This does not make much sense anymore since

1. generated clients are all located under generated/src source tree
2. c2j file renaming logic is extracted and duplicated within the code generation script run_code_generation.py, so additional logic of datetime extraction, c2j filename renaming and etc is not actually required in the cmake script.

i.e. cmake can rely solely on the source tree

tested by building both full main and this branch and by comparing the cmake output and resulting build/install directories, i.e.

tree ~/sdk-install-main-clean/ > mainTree.log
tree ~/sdk-install-cmake-refactor/ > refactorTree.log
diff mainTree.log refactorTree.log

Description of changes:

Check all that applies:

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

• Linux
• Windows
• Android
• MacOS
• IOS
• Other Platforms

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