docs: add docs build kokoro config for django spanner

[vi3k6i5]

docs: added docs build kokoro config for django spanner.

fixes #643

Docs will be published at link: https://googleapis.dev/python/django-google-spanner/latest/index.html

[busunkim96]

Some small comments on .repo-metadata.json, otherwise LGTM. :)

[vi3k6i5]

Some small comments on .repo-metadata.json, otherwise LGTM. :)

@busunkim96 : Fixed the comments, Thanks for the help :)

[busunkim96]

I think you'll need to copy https://github.com/googleapis/python-spanner/blob/master/.trampolinerc into this repo as well. I triggered the docs job manually and it appears to be failing on a missing bucket name: log

[vi3k6i5]

I think you'll need to copy https://github.com/googleapis/python-spanner/blob/master/.trampolinerc into this repo as well. I triggered the docs job manually and it appears to be failing on a missing bucket name: log

Added the same file, thanks

[busunkim96]

Looks like the docs jobs is all good now! You should see them at googleapis.dev/python/django-spanner-google/latest in a bit. :) docs job log

[busunkim96]

Docs are live! https://googleapis.dev/python/django-google-spanner/latest/index.html

FYI If you want to view the docs locally, you can run nox -s docs and open docs/_build/html in a browser.

[larkee]

I can see the docs at the given link so this LGTM 👍