Fix markup and minor grammar improvements in Code_of_conduct.md (GH-13640)

The old link had a > in the url which prevented the browser from jumping down to the correct section on that page.

That PSF page itself has an error: There's a duplicate "the" in that paragraph that needs to be removed: "...and conform to **the the** Python Community Code of Conduct."

While I was editing this file, I also fixed some grammar and bolded the 3 important keywords so that they catch the viewer's eyes. I can revert these changes if they are unwanted.

Thanks.

CODE_OF_CONDUCT.md

@@ -2,11 +2,11 @@
 
 Please note that all interactions on
 [Python Software Foundation](https://www.python.org/psf-landing/)-supported
-infrastructure is [covered](https://www.python.org/psf/records/board/minutes/2014-01-06/#management-of-the-psfs-web-properties>)
+infrastructure is [covered](https://www.python.org/psf/records/board/minutes/2014-01-06/#management-of-the-psfs-web-properties)
 by the [PSF Code of Conduct](https://www.python.org/psf/codeofconduct/),
-which includes all infrastructure used in the development of Python itself
+which includes all the infrastructure used in the development of Python itself
 (e.g. mailing lists, issue trackers, GitHub, etc.).
 
-In general this means everyone is expected to be open, considerate, and
-respectful of others no matter what their position is within the project.
+In general, this means that everyone is expected to be **open**, **considerate**, and
+**respectful** of others no matter what their position is within the project.