Mark addons in deletion

[maciaszczykm]

What this PR does / why we need it:

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged):
Fixes #2650

Special notes for your reviewer:

Release note:

Display deletion state of accessible addons.

[kubermatic-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: maciaszczykm

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• OWNERS [maciaszczykm]

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[maciaszczykm]

/assign @kgroschoff @floreks

[codecov]

Codecov Report

Merging #2674 into master will decrease coverage by 0.01%.
The diff coverage is 0.00%.

@@            Coverage Diff             @@
##           master    #2674      +/-   ##
==========================================
- Coverage   52.42%   52.41%   -0.02%     
==========================================
  Files         234      234              
  Lines        8213     8215       +2     
  Branches      990      991       +1     
==========================================
  Hits         4306     4306              
- Misses       3904     3906       +2     
  Partials        3        3              

Impacted Files	Coverage Δ
...ared/components/addon-list/addon-list.component.ts	19.56% <0.00%> (-0.44%)	⬇️

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[floreks]

/lgtm

[kubermatic-bot]

LGTM label has been added.

Git tree hash: 1e36a6a7c47e98c1d77a2b15ed18fd37750aae53

[floreks]

/lgtm

[kubermatic-bot]

LGTM label has been added.

Git tree hash: 51d394984aa6bf1a57ab2f6d2ba3e47e47dc3bb9