Readme Edits | Just cleanup edits

[wi-ski]

Why are these changes needed?

Minor english/grammar errors - corrected during project exploration

Related issue number

No issue.

Checks

• [x] I've included any doc changes needed for https://microsoft.github.io/autogen/. See https://microsoft.github.io/autogen/docs/Contribute#documentation to build and test documentation locally.
• [x] I've added tests (if relevant) corresponding to the changes introduced in this PR.
• [x] I've made sure all auto checks have passed.

[wi-ski]

@microsoft-github-policy-service agree