Add batch option to ddev dep updates command

[sarah-witt]

What does this PR do?

Adds a batch options to ddev dep updates command, so now you can specify the maximum number of dependencies to upgrade.

Motivation

It can be helpful to only update a few dependencies at a time, since it's easier to test, and there are less changes to focus on at once.

Additional Notes

Review checklist (to be filled by reviewers)

• Feature or bugfix MUST have appropriate tests (unit, integration, e2e)
• PR title must be written as a CHANGELOG entry (see why)
• Files changes must correspond to the primary purpose of the PR as described in the title (small unrelated changes should have their own PR)
• PR must have changelog/ and integration/ labels attached

[codecov]

Codecov Report

Merging #10229 (66ffaee) into master (c28729a) will not change coverage.
The diff coverage is n/a.

Flag	Coverage Δ
datadog_checks_dev	80.32% <ø> (ø)

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[ofek]

Wouldn't this always exit after the first loop by default?

[sarah-witt]

Wouldn't this always exit after the first loop by default?

Whoops, updated to handle that case!