Use isQualifierConvertible in isInputRange!(R, E)

[pbackus]

This replaces the bespoke type comparison that was previously used. All conversions allowed by the previous version are still allowed after this change.

See #8828 and related threads for discussion.

[dlang-bot]

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If your PR contains non-trivial changes, please reference a Bugzilla issue or create a manual changelog.

Testing this PR locally

If you don't have a local development environment setup, you can use Digger to test this PR:

dub run digger -- build "master + phobos#8830"

[Imperatorn]

styleCheck etc std -I.
std/range/primitives.d(183:11)[warn]: Variable "isInputRange" has the same name as a variable defined on line 175.
make: *** [posix.mak:587: dscanner] Error 1
🚨 Error: The command exited with status 2

[pbackus]

Apparently this is a known issue with D-Scanner: dlang-community/D-Scanner#323

Looks like a bunch of modules in Phobos already have this check disabled, probably for this exact reason. I'll add std.range.primitives to the list.