Remove the assumption on Language being found and understood

[Jym77]

All rules with Language as input aspect had an assumption about it being determined and understood.
This assumption is moved to the Input aspects document (w3c/wcag-act#521 even though it seems to not be published yet 🤔 ) So we can remove it from the individual rules.

This should probably not be merged before the change in input aspects got published.

Closes issue(s):

• N/A

Need for Call for Review:
This will require a 1 week Call for Review (moving an assumption to a shared document).

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[daniel-montalvo]

Just these minor grammar and consistency issues for your consideration. Will approve when addressed.

[Jym77]

@daniel-montalvo All these are about existing assumptions that are not touched by this PR. As much as I agree the changes are needed, I also think that we shouldn't do them as part of this PR in order to keep things focused (the PR is already touching a lot of rules, so I'd prefer keeping it focused on doing one thing).

[daniel-montalvo]

@daniel-montalvo All these are about existing assumptions that are not touched by this PR. As much as I agree the changes are needed, I also think that we shouldn't do them as part of this PR in order to keep things focused (the PR is already touching a lot of rules, so I'd prefer keeping it focused on doing one thing).

Fair enough. Let's then go ahead with as-is and keep the others for later.

[Jym77]

Waiting for w3c/wcag-act#521 to be published before merging this one.
It is currently in the Editor's draft version, but not in the published one.

Publishing the input aspect might be delayed until #1783 is solved.

[Jym77]

The new version of the Input aspects has been published.
Merging this.