[Feature Request] Increase simultaneous dependabot version bumps

Is your feature request related to a problem? Please describe

Dependabot is currently configured to have only one open version bump PR per module, with weekly updates. For example, here is the configuration for repository-azure
https://github.com/opensearch-project/OpenSearch/blob/9bef705d321d83b37f92292662c80a5e0cb4ba66/.github/dependabot.yml#L950-L954

While this appears intended to reduce PR spam from version bumps, it has an unfortunate side effect. When a version bump is stalled for some reason, no other version bumps go through. See for example:

• https://github.com/opensearch-project/OpenSearch/pull/17059 (Jan 20), superceded by
• https://github.com/opensearch-project/OpenSearch/pull/17562 (today)

This is significant because the version of a completely different dependency was never bumped, despite being needed to resolve CVE-2024-57699, published Feb 5 (33 days ago).

Describe the solution you'd like

Increase the limit of open PRs to 2, to prevent a single stalled version bump from blocking all others for a module.

Related component

Libraries

Describe alternatives you've considered

• Change dependency management to Mend Remediate. While the same PR throttling limits (and more flexibility) is included, it provides a "Dependency Dashboard" where one can also view pending PRs which have been throttled, and click a box to request a PR; a good workflow to establish in the run-up to a release when fixing CVEs should be a priority.
• Investigate any other way to prioritize CVE-fixing version bumps

Additional context

No response

Inspect .github/dependabot.yml around lines 950-954, where the repository-azure configuration limits open version-bump pull requests. Update the limit from one to two and verify that the Dependabot configuration remains valid; the requested behavior is allowing two simultaneous version-bump PRs per module.