[SDK-2032] Create Github Action to merge dependabot PRs

[nsingh-branch]

Reference

SDK-2032 -- Create GHA to auto-merge Dependabot PRs to test branch

Summary

Created new GHA workflow that creates a new testing branch with all of the open PRs from Dependabot, then notifies the team in Slack.

Motivation

To make it easier to manage incoming Dependabot PRs by automatically creating test branches and notifying the team

Type Of Change

• [x] New feature (non-breaking change which adds functionality)

Testing Instructions

Manually run the GHA and check the test branch it creates for all of the open Dependabot PRs.

cc @BranchMetrics/saas-sdk-devs for visibility.

[github-actions[bot]]

Test Results

112 tests   105 :heavy_check_mark:  1m 7s :stopwatch:     1 suites      7 :zzz:     1 files        0 :x:

Results for commit a49e823e.

:recycle: This comment has been updated with latest results.

[codecov[bot]]

Codecov Report

:exclamation: No coverage uploaded for pull request base (master@6973916). Click here to learn what that means. The diff coverage is n/a.

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