Ignore context cancell in status reporting

[michalpristas]

What does this PR do?

Followup to #27210
This PR reduces context cancelled from status reporting including cases when process itself reports failure due to context cancelled.

Result is that two messages described in a comment linked below will disappear.
These does not alter behaviour and occur just at the time of restarting. But it may look like there's something wrong with process, operator or agent itself as failures propagate up.

Why is it important?

Fixes: #27062 (comment)

Checklist

• My code follows the style guidelines of this project
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• I have made corresponding change to the default configuration files
• I have added tests that prove my fix is effective or that my feature works
• I have added an entry in CHANGELOG.next.asciidoc or CHANGELOG-developer.next.asciidoc.

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• Start Time: 2021-08-31T14:59:53.315+0000

• Duration: 138 min 22 sec

• Commit: c0ab917

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Test	Results
Failed	0
Passed	24797
Skipped	1635
Total	26432

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Test stats 🧪

Test	Results
Failed	0
Passed	24797
Skipped	1635
Total	26432

[blakerouse]

Looks good.