Support chopprefix/chopsuffix returning InlineString

[nickrobinson251]

In Julia v1.8 we now have chopprefix and chopsuffix

Because they're implemented in terms of iterate, they already work on InlineString types but they return a SubString whereas, like with chop/chomp, we could instead be returning an InlineString e.g.

julia> s = "hey_there_";

julia> si = InlineString(s);

julia> chopsuffix(s, "_")
"hey_there"

julia> chopsuffix(si, "_")  # correct answer, but...
"hey_there"

julia> typeof(ans)          # unexpected type (SubString)
SubString{String15}

julia> chop(si)             # for comparison...
"hey_there"

julia> typeof(ans)          # returns InlineString (not SubString)
String15

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related: #5