maintainer:release-notes requires tag or SHA for ref2

[greggles]

The help for maintainer:release-notes says the arguments can be branches.

  ref1                   Git tag, branch, or SHA
  ref2                   Git tag, branch, or SHA [default: "HEAD"]

In my testing, using a tag for ref1 and a branch for ref2 did not work:

❰gknaddison❙~/checkouts/openid_connect(git:8.x-1.x)❱✔≻ drupalorg mrn 8.x-1.0-beta5 8.x-1.x
The 8.x-1.x tag is not valid.
❰gknaddison❙~/checkouts/openid_connect(git:8.x-1.x)❱✘≻ git branch -v
* 8.x-1.x e002d7e Revert "Issue #2961752: Replace 'drupal_set_message()' with messenger service in redirect controller and accounts form." This reverts commit 11d078fc4055f048fa134eaef10458a147c52f97.
❰gknaddison❙~/checkouts/openid_connect(git:8.x-1.x)❱✔≻

I guess the easiest way to achieve what I was trying to do is just run it without ref2, e.g. drupalorg mrn 8.x-1.0-beta5 did exactly what I wanted to achieve.

I think it could be OK to just update the docs to remove mention of branches if they are not supported.

[mglaman]

Honestly, I just forgot to finish the feature. I would want it to work against branches and tags. Currently it hard checks tags. I would like it to work similar to you'd expect Git to: OBJECT...OBJECT

[greggles]

Sounds good, then I guess this is a feature request for that.