Update MANIFEST.in

[kelibezhani]

Update MANIFEST.in to include requirements.txt file.

[sonarcloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
No data about Coverage
0.0% Duplication on New Code

See analysis details on SonarCloud

[amplify-self-hosted-runners]

Check Name	Conclusion	Summary	Output
SonarCloud Code Analysis	success	Quality Gate passed	output
Mend Security Check	neutral	Security Report	output
Mend License Check	neutral	License Report	output
Verify that version was updated	success	Verify that version was updated	output
Check code against linter/unit tests (3.7)	success	Check code against linter/unit tests (3.7)	output
Check code against linter/unit tests (3.8)	success	Check code against linter/unit tests (3.8)	output
Check code against linter/unit tests (3.9)	success	Check code against linter/unit tests (3.9)	output
pre-commit	success	pre-commit	output