Docs: README.md doesn't include login info

[bookdude13]

When setting up a development environment using Docker and the instructions in README.md, I noticed that the login credentials are not mentioned. I guessed the correct ones (admin/password), but this should be included in that file.

[bookdude13]

Note that this only applies to the SVN checkout, since the Git mirror doesn't contain README.md

[SergeyBiryukov]

Hi there, welcome to WordPress Trac! Thanks for the ticket.

Replying to bookdude13:

Note that this only applies to the SVN checkout, since the Git mirror doesn't contain README.md

This one does: ​https://github.com/WordPress/wordpress-develop/

[bookdude13]

I forget which repo I was using, but that wasn't it. That's helpful, thanks :-)

Replying to SergeyBiryukov:

Hi there, welcome to WordPress Trac! Thanks for the ticket.

Replying to bookdude13:

Note that this only applies to the SVN checkout, since the Git mirror doesn't contain README.md

This one does: ​https://github.com/WordPress/wordpress-develop/

[bookdude13]

Updated README.md

[bookdude13]

Also, thanks for the welcome @SergeyBiryukov!

README.md updated. I also mentioned the default site address (localhost:8889). Let me know if other keywords are supposed to change (not doing needs-testing since it's just docs).

[johnbillion]

In 47744:

Build/Test Tools: Add information regarding the default credentials for the local development environment to the project readme.

Props bookdude13

Fixes #49273