Update dependabot.yml to include github-actions updates

[cwperks]

Description

Updating dependabot.yml to also scan for outdated github actions. This is modeled after the dependabot.yml file in the security plugin: https://github.com/opensearch-project/security/blob/main/.github/dependabot.yml

This will also skip major version upgrades of dependencies which may involve more work then minor or patch version upgrades.

Check List

• New functionality includes testing.
  • All tests pass
• New functionality has been documented.
  • New functionality has javadoc added
• Commits are signed per the DCO using --signoff

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.
For more information on following Developer Certificate of Origin and signing off your commits, please check here.

[codecov]

Codecov Report

Merging #488 (a473206) into main (14eae94) will not change coverage.
The diff coverage is n/a.

@@            Coverage Diff            @@
##               main     #488   +/-   ##
=========================================
  Coverage     29.17%   29.17%           
  Complexity       98       98           
=========================================
  Files            22       22           
  Lines          1186     1186           
  Branches        109      109           
=========================================
  Hits            346      346           
  Misses          819      819           
  Partials         21       21           

📢 Have feedback on the report? Share it here.

[dbwiddis]

LGTM although I love to evangelize Mend Renovate as a dependabot alternative (which does this automatically) and just requires editing the .whitesource file.

[opensearch-trigger-bot]

The backport to 2.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 working tree
git worktree add .worktrees/backport-2.x 2.x
# Navigate to the new working tree
cd .worktrees/backport-2.x
# Create a new branch
git switch --create backport/backport-488-to-2.x
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick -x --mainline 1 57135244ef30e85338f735860d67fa8dbc795a57
# Push it to GitHub
git push --set-upstream origin backport/backport-488-to-2.x
# Go back to the original working tree
cd ../..
# Delete the working tree
git worktree remove .worktrees/backport-2.x

Then, create a pull request where the base branch is 2.x and the compare/head branch is backport/backport-488-to-2.x.