Add panicking helpers for getting components from Query

[Shatur]

Objective

• Currently we don't have panicking alternative for getting components from Query like for resources. Partially addresses Add panicking versions of get_component and get #9443.

Solution

• Add these functions.

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Changelog

Added

• Query::component and Query::component_mut to get specific component from query and panic on error.

[alice-i-cecile]

The "See also" section of the docs should point to the non-panicking equivalents, and vice versa :)

[Shatur]

The "See also" section of the docs should point to the non-panicking equivalents, and vice versa :)

Currently we points from mut functions to non-mut equivalents. I can add pointing to non-panicking equivalents, but it will be 2 additional functions (mut and non-mut one). So should I point to 3 other functions?
Or should I only cross-reference panicking and non-panicking equivalents?
Please, advice :)

[alice-i-cecile]

I would point to the adjacent functions in the panicking/mutability grid :) So each should reference two other methods.

[Shatur]

@alice-i-cecile makes sense, done!

[alice-i-cecile]

@Shatur, thinking about this a bit more, this should also exist on QueryState, and we should call the corresponding method from Query.

[Shatur]

@alice-i-cecile hm... I don't see get_component in QueryState. Should I open a separate issue to add them or add (get_)component(_mut) here?

[alice-i-cecile]

Separate issue to add them then please :)

[Shatur]

@alice-i-cecile done: #9683