[Feature Request] Configure rebasing strategy for dependabot created PRs

Is your feature request related to a problem? Please describe

Majorly with version upgrades, the PR becomes stale and a maintainer needs to manually trigger @dependabot recreate to recreate the PR. Also, with backport PRs the major concerns are with resolving merge conflicts manually because of the tagret/source branch are out of sync.

Describe the solution you'd like

Configuring up rebase-strategy in these cases can help reduce the manual involvement and dependency on maintainers to rebase changes.

Related component

Build

Describe alternatives you've considered

Can use default configuration which is rebase-strategy: auto. Also, can configure it to reduce the frequency of rebasing.

Not sure if we can do the same with opensearch-trigger-bot or not. Presently, as of 9/26, we have 20 open PRs from both these bots combined.

Additional context

This can potentially help us move version upgrades & backport PRs move a lot faster and will certainly reduce the backlog we have built with so many version upgrade languishing PRs.