Render disabled mxField textareas as disabled

[turt2live]

Fixes element-hq/element-web#8440

[jryans]

Styling label as well seems good... but surely we should do the same for select and input labels as well?

[turt2live]

We don't seem to need to in order to get the disabled effect.

[jryans]

Hmm, but for example the theme dropdown's label in Settings doesn't seem disabled...?

[turt2live]

It looked fairly disabled to me :(

I'll double check all the browsers again, and probably flip a table doing it.

[jryans]

Firefox on macOS looks like:

which seems to have the label color #454545 (normal) and not #888 (greyed, as would be used here if extended).

[turt2live]

@jryans please take another look. For reference, here's a giant blob of examples:

<Field id={"one"} type={"text"} label={"Enabled Text"}/>
<Field id={"one"} type={"text"} label={"Disabled Text"} disabled={true}/>
<Field id={"one"} type={"text"} label={"Enabled Text"} placeholder={"Enabled text with placeholder"}/>
<Field id={"one"} type={"text"} label={"Disabled Text"} disabled={true} placeholder={"Disabled text with placeholder"}/>
<Field id={"one"} type={"text"} label={"Enabled Text"} value={"with value"}/>
<Field id={"one"} type={"text"} label={"Disabled Text"} disabled={true} value={"with value"}/>

<Field id={"one"} type={"password"} label={"Enabled Password"}/>
<Field id={"one"} type={"password"} label={"Disabled Password"} disabled={true}/>
<Field id={"one"} type={"password"} label={"Enabled Password"} placeholder={"Enabled password with placeholder"}/>
<Field id={"one"} type={"password"} label={"Disabled Password"} disabled={true} placeholder={"Disabled password with placeholder"}/>
<Field id={"one"} type={"password"} label={"Enabled Password"} value={"with value"}/>
<Field id={"one"} type={"password"} label={"Disabled Password"} disabled={true} value={"with value"}/>

<Field id={"one"} element={"textarea"} label={"Enabled Textarea"}/>
<Field id={"one"} element={"textarea"} label={"Disabled Textarea"} disabled={true}/>
<Field id={"one"} element={"textarea"} label={"Enabled Textarea"} placeholder={"Enabled textarea with placeholder"}/>
<Field id={"one"} element={"textarea"} label={"Disabled Textarea"} disabled={true} placeholder={"Disabled textarea with placeholder"}/>
<Field id={"one"} element={"textarea"} label={"Enabled Textarea"} value={"with value"}/>
<Field id={"one"} element={"textarea"} label={"Disabled Textarea"} disabled={true} value={"with value"}/>

<Field id={"one"} element={"select"} label={"Enabled Select"}><option>First Option</option></Field>
<Field id={"one"} element={"select"} label={"Disabled Select"} disabled={true}><option>First Option</option></Field>

[jryans]

This seems correct to me, thanks! 😁

[turt2live]

I'm merging this because the test breakages are unrelated and I don't want to wait another hour in the CI queue.