fix(module:code-editor): run value changes in Angular zone

[Airblader]

Since monaco is initialized outside the Angular zone, the onDidChangeContent
method will inherit this and therefore no change detection ends up being
triggered. This can cause e.g. validation tips to be shown with a delay
(only once another change detection cycle comes along).

Therefore we run the callback explicitly inside the Angular zone.

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Please check if your PR fulfills the following requirements:

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• 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:

[zorro-bot]

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[Airblader]

CC @hsuanxyz @simplejason We came across this in our product.

[codecov]

Codecov Report

Merging #5872 into master will decrease coverage by 0.02%.
The diff coverage is 0.00%.

@@            Coverage Diff             @@
##           master    #5872      +/-   ##
==========================================
- Coverage   90.03%   90.01%   -0.03%     
==========================================
  Files         463      463              
  Lines       13920    13921       +1     
  Branches     2201     2201              
==========================================
- Hits        12533    12531       -2     
- Misses        853      855       +2     
- Partials      534      535       +1     

Impacted Files	Coverage Δ
components/code-editor/code-editor.component.ts	13.00% <0.00%> (-0.14%)	⬇️
components/core/util/text-measure.ts	89.56% <0.00%> (-1.74%)	⬇️

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[wzhudev]

@hsuanxyz Please check schematic testing. @angular/cdk updated yesterday and seemed introducing a breaking change.

[hsuanxyz]

@wendellhu95 I'm in the hospital, check it later today, it may be caused by the CDK version

[github-actions]

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