Change some values from secrets to variables, for example PANTHEON_SITE_NAME

[YesCT]

https://github.com/Lullabot/drainpipe?tab=readme-ov-file#pantheon

Change some values from secrets to variables

PANTHEON_SITE_NAME seems a candidate for a variable. Are there any reasons to have it be a secret?

TERMINUS_PLUGINS also?

any others?

[YesCT]

Having a variable allows inspecting it's value. Easier for debugging.

[davereid]

+1 for using a variable for PANTHEON_SITE_NAME since it's not a secret. I also have some code I could use from a prior project that makes setting that very optional based on reading from the Github repository name or the DDEV config file.

[justafish]

https://github.com/Lullabot/drainpipe/blob/main/scaffold/github/workflows/PantheonReviewAppsDDEV.yml#L45
apparently we can change this to e.g. ${{ vars.PANTHEON_SITE_NAME || secrets.PANTHEON_SITE_NAME }} to maintain backwards compatability