[nr-k8s-otel-collector] chore: update common-library to 1.4.0

[kondracek-nr]

What this PR does / why we need it:

Updates common-library chart to 1.4.0 for nr-k8s-otel-collector, which enforces the use of fully-qualified image names by setting docker.io as the explicit default registry when no other registry is provided.

Broke this out from #2040 because trying to get all the necessary approvals before I had to rebase from the master branch was driving me nuts.

Opening as draft for now as there are other common-library PRs in line.

Which issue this PR fixes

(optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close that issue when PR gets merged)

• fixes #

Special notes for your reviewer:

Checklist

[Place an '[x]' (no spaces) in all applicable fields. Please remove unrelated fields.]

• Chart Version bumped
• Variables are documented in the README.md
• Title of the PR starts with chart name (e.g. [mychartname])

Release Notes to Publish (nr-k8s-otel-collector)

If this PR contains changes in nr-k8s-otel-collector, please complete the following section. All other charts should ignore this section.

🚀 What's Changed

• Updates common-library to 1.4.0, which enforces the use of fully-qualified image paths