docs: truncated sentence

[CAD97]

"About parts - Snapcraft 9.0 documentation".

I think you a word

8.17 had a full sentence:

"payload, either individually or as part of a larger project containing many components." should be "A part is a description of the components to be built and prepared for deployment in a payload, either individually or as part of a larger project containing many components.".

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Reported from: https://documentation.ubuntu.com/snapcraft/9.0/explanation/parts/

[Jha-2022]

I would like to fix this issue but while editing it, I found out that its actually dynamicaly pulling content from external repo named as "craft-parts"