Alerting: Fix stats that display alert count when using unified alerting

[gotjosh]

These stats are incorrect when using unified alerting as they query the legacy alert rule table. Now, we conditionally query one of the other.

TODO

• Tests
• figure out the config nil check - why do we have this in ngalert?

[grafanabot]

Hello @gotjosh!
Backport pull requests need to be either:

• Pull requests which address bugs,
• Urgent fixes which need product approval, in order to get merged,
• Docs changes.

Please, if the current pull request addresses a bug fix, label it with the type/bug label.
If it already has the product approval, please add the product-approved label. For docs changes, please add the type/docs label.
If none of the above applies, please consider removing the backport label and target the next major/minor release.
Thanks!

[grafanabot]

This pull request was removed from the 9.4.6 milestone because 9.4.6 is currently being released.

[JacobsonMT]

LGTM 🚀

[alexweav]

LGTM overall.

I guess this view is not per-org? Also, I was originally hesitant to capture the entire setting.Cfg for one field, but this service does span many areas... so that's probably OK.

[gotjosh]

I guess this view is not per-org? Also, I was originally hesitant to capture the entire setting.Cfg for one field

Is there a way in which I can import only the boolean? I'd think there isn't given the "settings" struct needs to be provided directly.

[grafanabot]

This pull request was removed from the 9.4.7 milestone because 9.4.7 is currently being released.

[grafanabot]

The backport to v9.4.x failed:

Server Error

To backport manually, run these commands in your terminal:

# Fetch latest updates from GitHub
git fetch
# Create a new branch
git switch --create backport-64852-to-v9.4.x origin/v9.4.x
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick -x 02a8f62021750b0af6dd8760ca2516e5e285a998
# Push it to GitHub
git push --set-upstream origin backport-64852-to-v9.4.x
git switch main
# Remove the local backport branch
git branch -D backport-64852-to-v9.4.x

Then, create a pull request where the base branch is v9.4.x and the compare/head branch is backport-64852-to-v9.4.x.

[grafanabot]

The backport to v9.4.x failed:

The process '/usr/bin/git' failed with exit code 1

To backport manually, run these commands in your terminal:

# Fetch latest updates from GitHub
git fetch
# Create a new branch
git switch --create backport-64852-to-v9.4.x origin/v9.4.x
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick -x 02a8f62021750b0af6dd8760ca2516e5e285a998
# Push it to GitHub
git push --set-upstream origin backport-64852-to-v9.4.x
git switch main
# Remove the local backport branch
git branch -D backport-64852-to-v9.4.x

Then, create a pull request where the base branch is v9.4.x and the compare/head branch is backport-64852-to-v9.4.x.