If the base type is composed with marker protocol(s) i.e.
`<<Type>> & Sendable`, let's skip this check because such
compositions are always opened and simplified down to a
superclass bound post-Sema.
Resolves: rdar://148782046
The original check introduced by https://github.com/apple/swift/pull/71855
is too broad. For concrete metadata we call the runtime demangler so
we need to strip off marker protocols when mangling that string and
`mangleTypeForReflection` already does that.
