feat(cli/args): implement --deny-import flag

[sgasho]

Closes: #29502

Preparing deny_import.js like below,

import "https://deno.land/std@0.201.0/log/mod.ts";
console.log("hello");

I verified that these changes were working properly by running the following command: ~/denoland/deno/target/debug/deno run --deny-import="example.com:443,deno.land:443" deny_import.js shows an import access error like the one below.

I also verified that ~/denoland/deno/target/debug/deno run --deny-import="example.com:443" deny_import.js does not show any errors because example.com is not referenced in deny_import.js

[anonhostpi]

ANNOTATION: simply a clone of the allow_import_arg behavior from the lines above it:

deno/cli/args/flags.rs

Lines 4084 to 4095 in 724685c

	.arg(
	{
	let mut arg = allow_import_arg().hide(true);
	if let Some(requires) = requires {
	// allow this for install --global
	if requires != "global" {
	arg = arg.requires(requires)
	}
	}
	arg
	}
	)

[sgasho]

deny_import_arg behavior is a bit different from allow_import_arg.

Do you mean that I should extract line 4099-4104 as a method?

Or, am I missing something...

[anonhostpi]

No just commenting on the diff. The behavior here wasn't exactly obvious and highlighed well by the diff.

If you were curious, I initially didn't understand the // allow ... comment until I looked at the undiffed file and realized it was a copy and paste.