fix(module:i18n): added missing translations to pl_PL

[TheMadMattt]

Added translations related with date picker and calendar for week and range placeholders

PR Checklist

Please check if your PR fulfills the following requirements:

• The commit message follows our guidelines: https://github.com/NG-ZORRO/ng-zorro-antd/blob/master/CONTRIBUTING.md#commit
• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)

PR Type

What kind of change does this PR introduce?

[X] Bugfix
[ ] Feature
[ ] Code style update (formatting, local variables)
[ ] Refactoring (no functional changes, no api changes)
[ ] Build related changes
[ ] CI related changes
[ ] Documentation content changes
[ ] Application (the showcase website) / infrastructure changes
[ ] Other... Please describe:

What is the current behavior?

Issue Number: N/A

What is the new behavior?

Does this PR introduce a breaking change?

[ ] Yes
[X] No

Other information

[zorro-bot]

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[codecov]

Codecov Report

Merging #7950 (aee4bd6) into master (100796c) will increase coverage by 0.01%.
The diff coverage is n/a.

❗ Current head aee4bd6 differs from pull request most recent head 52b2d20. Consider uploading reports for the commit 52b2d20 to get more accurate results

@@            Coverage Diff             @@
##           master    #7950      +/-   ##
==========================================
+ Coverage   91.73%   91.74%   +0.01%     
==========================================
  Files         509      509              
  Lines       17447    17447              
  Branches     2685     2685              
==========================================
+ Hits        16005    16007       +2     
+ Misses       1144     1142       -2     
  Partials      298      298              

see 1 file with indirect coverage changes