Consider compiling iOS CHIPTool in CI

[bzbarsky-apple]

Reproduction steps

Right now nothing in CI builds iOS CHIPTool.

Bug prevalence

Always.

GitHub hash of the SDK that was being used

b10a85a

Platform

darwin

Platform Version(s)

No response

Anything else?

No response

[bzbarsky-apple]

When I try the obvious:

cd src/darwin/CHIPTool

xcodebuild -target "CHIPTool" -sdk iphoneos -configuration Release

I get:

src/darwin/CHIPTool/CHIPTool.xcodeproj: error: Signing for "CHIPTool" requires a development team. Select a development team in the Signing & Capabilities editor. (in target 'CHIPTool' from project 'CHIPTool')

[bzbarsky-apple]

And this:

 xcodebuild -target CHIPTool -sdk iphoneos -configuration Release CODE_SIGN_IDENTITY="" CODE_SIGNING_REQUIRED=NO

returns:

error: src/darwin/CHIPTool/build/Release-iphoneos/Matter.framework: No such file or directory (in target 'CHIPTool' from project 'CHIPTool')

which is getting closer...