[4.4] Small spelling correction in dock blocks

[pe7er]

Summary of Changes

I bumped into a double "the the" in a dock block and found more of those.
This small PR corrects some double "the the" instances.
It also corrects some double "of of", "to to" and "for for" instances.

The language string PLG_SAMPLEDATA_TESTING_SAMPLEDATA_CONTENT_ARTICLE_00_INTROTEXT that I corrected had a double "to to".

No test necessary, code review only.

Link to documentations

Please select:

• Documentation link for docs.joomla.org:

• No documentation changes for docs.joomla.org needed

• Pull Request link for manual.joomla.org:

• No documentation changes for manual.joomla.org needed

[Quy]

I have tested this item ✅ successfully on 978bcfc

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[chmst]

I have tested this item ✅ successfully on 978bcfc

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_{This comment was created with the J!Tracker Application at issues.joomla.org/tracker/joomla-cms/43628.}

[Quy]

RTC

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[MacJoom]

Thank you!