frontend: Add integration test for split and cache middleware

[julienduchesne]

This tests two aspects of the split and cache feature:

1. We can go above the partial query length (because queries are split)
2. The query is split into multiple 24h queries

This is in response to #10796

Checklist

• Tests updated.
• [N/A] Documentation added.
• [N/A] CHANGELOG.md updated - the order of entries should be [CHANGE], [FEATURE], [ENHANCEMENT], [BUGFIX].
• [N/A] about-versioning.md updated with experimental features.

[dimitarvdimitrov]

thanks

[aknuds1]

Testing the creation of a backport PR, please ignore.

[grafanabot]

The backport to r314 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-10798-to-r314 origin/r314
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick -x b561724131cab1ea2ec1333e4aa0886d5dda0e5a
# Push it to GitHub
git push --set-upstream origin backport-10798-to-r314
git switch main
# Remove the local backport branch
git branch -D backport-10798-to-r314

Then, create a pull request where the base branch is r314 and the compare/head branch is backport-10798-to-r314.

[grafanabot]

The backport to r330 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-10798-to-r330 origin/r330
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick -x b561724131cab1ea2ec1333e4aa0886d5dda0e5a
# Push it to GitHub
git push --set-upstream origin backport-10798-to-r330
git switch main
# Remove the local backport branch
git branch -D backport-10798-to-r330

Then, create a pull request where the base branch is r330 and the compare/head branch is backport-10798-to-r330.