fix(opm): adds removal of empty packages when using opm diff in headsOnly mode

[jpower432]

opm diff in headsOnly mode with an include config will prune all empty channels
from a package which can leave the output config with an empty package. This change
will remove any empty packages after the channel pruning.

Fixes #904

Signed-off-by: Jennifer Power barnabei.jennifer@gmail.com

Description of the change:
This PR removes empty packages when using opm alpha diff with no previous reference.

Motivation for the change:
To ensure file-based catalogs are not being created with invalid packages by opm alpha diff

Reviewer Checklist

• Implementation matches the proposed design, or proposal is updated to match implementation
• Sufficient unit test coverage
• Sufficient end-to-end test coverage
• Docs updated or added to /docs
• Commit messages sensible and descriptive

[openshift-ci]

Hi @jpower432. Thanks for your PR.

I'm waiting for a operator-framework member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

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[codecov]

Codecov Report

Merging #905 (a9d2c64) into master (c056ac1) will increase coverage by 0.09%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master     #905      +/-   ##
==========================================
+ Coverage   52.07%   52.17%   +0.09%     
==========================================
  Files         103      103              
  Lines        9092     9094       +2     
==========================================
+ Hits         4735     4745      +10     
+ Misses       3449     3443       -6     
+ Partials      908      906       -2     

Impacted Files	Coverage Δ
alpha/declcfg/diff.go	77.96% <100.00%> (+1.04%)	⬆️
pkg/registry/query.go	60.41% <0.00%> (-0.53%)	⬇️
alpha/declcfg/diff_include.go	67.92% <0.00%> (+6.60%)	⬆️

---

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[dinhxuanvu]

/approve

[openshift-ci]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: dinhxuanvu, jpower432

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• OWNERS [dinhxuanvu]

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[dinhxuanvu]

/ok-to-test

[joelanford]

/lgtm