fix: Improve docs for min and max table offsets

[salvacorts]

What this PR does / why we need it:
The docs for min and max offsets are a bit difficult to reason about. This PR improves them with examples and sets the default min offset to 0 (build from today), and the max to 1 (build till tomorrow).

We also add a test for the tables iterator.

Checklist

• Reviewed the CONTRIBUTING.md guide (required)
• Documentation added
• Tests updated
• Title matches the required conventional commits format, see here
  • Note that Promtail is considered to be feature complete, and future development for logs collection will be in Grafana Alloy. As such, feat PRs are unlikely to be accepted unless a case can be made for the feature actually being a bug fix to existing behavior.
• Changes that require user attention or interaction to upgrade are documented in docs/sources/setup/upgrade/_index.md
• If the change is deprecating or removing a configuration option, update the deprecated-config.yaml and deleted-config.yaml files respectively in the tools/deprecated-config-checker directory. Example PR

[chaudum]

Should we increase the default to 7? I think this would make sense in the broader context

[salvacorts]

I'm hesitant to do that until we get more confident about how good the build process scales. If data doesn't change as often, building today + tomorrow should work more most of the cases.

[chaudum]

Ok with that

[loki-gh-app]

The backport to k227 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-14890-to-k227 origin/k227
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick -x fd9d33241d4a5cdf0066233bf8bdda69ea23a9f7

When the conflicts are resolved, stage and commit the changes:

git add . && git cherry-pick --continue

If you have the GitHub CLI installed:

# Push the branch to GitHub:
git push --set-upstream origin backport-14890-to-k227
# Create the PR body template
PR_BODY=$(gh pr view 14890 --json body --template 'Backport fd9d33241d4a5cdf0066233bf8bdda69ea23a9f7 from #14890{{ "\n\n---\n\n" }}{{ index . "body" }}')
# Create the PR on GitHub
echo "${PR_BODY}" | gh pr create --title 'fix: Improve docs for min and max table offsets (backport k227)' --body-file - --label 'size/M' --label 'type/docs' --label 'backport' --base k227 --milestone k227 --web

Or, if you don't have the GitHub CLI installed (we recommend you install it!):

# Push the branch to GitHub:
git push --set-upstream origin backport-14890-to-k227

# Create a pull request where the `base` branch is `k227` and the `compare`/`head` branch is `backport-14890-to-k227`.

# Remove the local backport branch
git switch main
git branch -D backport-14890-to-k227

[loki-gh-app]

The backport to k227 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-14890-to-k227 origin/k227
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick -x fd9d33241d4a5cdf0066233bf8bdda69ea23a9f7

When the conflicts are resolved, stage and commit the changes:

git add . && git cherry-pick --continue

If you have the GitHub CLI installed:

# Push the branch to GitHub:
git push --set-upstream origin backport-14890-to-k227
# Create the PR body template
PR_BODY=$(gh pr view 14890 --json body --template 'Backport fd9d33241d4a5cdf0066233bf8bdda69ea23a9f7 from #14890{{ "\n\n---\n\n" }}{{ index . "body" }}')
# Create the PR on GitHub
echo "${PR_BODY}" | gh pr create --title 'fix: Improve docs for min and max table offsets (backport k227)' --body-file - --label 'size/M' --label 'type/docs' --label 'backport' --base k227 --milestone k227 --web

Or, if you don't have the GitHub CLI installed (we recommend you install it!):

# Push the branch to GitHub:
git push --set-upstream origin backport-14890-to-k227

# Create a pull request where the `base` branch is `k227` and the `compare`/`head` branch is `backport-14890-to-k227`.

# Remove the local backport branch
git switch main
git branch -D backport-14890-to-k227