Fix add rbac dialog styling

[floreks]

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 #2830

Release note:

Fixed styling of 'Add RBAC Binding' dialog.

[kubermatic-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: floreks

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[codecov]

Codecov Report

Merging #2850 (9df9df1) into master (54f37b7) will increase coverage by 0.13%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #2850      +/-   ##
==========================================
+ Coverage   52.35%   52.49%   +0.13%     
==========================================
  Files         234      234              
  Lines        8188     8197       +9     
  Branches      939      943       +4     
==========================================
+ Hits         4287     4303      +16     
+ Misses       3898     3892       -6     
+ Partials        3        2       -1     

Impacted Files	Coverage Δ
src/app/shared/utils/member-utils/member-utils.ts	83.33% <0.00%> (-1.52%)	⬇️
src/app/project/project.component.ts	73.16% <0.00%> (+3.89%)	⬆️

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[maciaszczykm]

/lgtm

[kubermatic-bot]

LGTM label has been added.

Git tree hash: e02ac692086c35cab7b497e2f8339478b9baecc7