`modernize-use-trailing-return-type` might show desugared type in fix-it hint for lamdba

[firewave]

Split from #144509.

#include <algorithm>
#include <vector>

void f()
{
    auto it2 = [](const std::vector<int>& v) {
        return std::find_if(v.cbegin(), v.cend(), [](int i) -> bool {
            return i == 0;
        });
    };
}

<source>:10:16: warning: use a trailing return type for this lambda [modernize-use-trailing-return-type]
   10 |     auto it2 = [](const std::vector<int>& v) {
      |                ^
      |                                              -> __gnu_cxx::__normal_iterator<const int *, std::vector<int>>

https://godbolt.org/z/zzYMa4o5r

It should be suggesting std::vector<int>::const_iterator.

[firewave]

I don's see the original sugared type preserved in the AST https://godbolt.org/z/farW8EqE3

Originally posted by @vbvictor in #144509

[llvmbot]

@llvm/issue-subscribers-clang-tidy

Author: Oliver Stöneberg (firewave)

Split from #144509.

#include <algorithm>
#include <vector>

void f()
{
    auto it2 = [](const std::vector<int>& v) {
        return std::find_if(v.cbegin(), v.cend(), [](int i) -> bool {
            return i == 0;
        });
    };
}

<source>:10:16: warning: use a trailing return type for this lambda [modernize-use-trailing-return-type]
   10 |     auto it2 = [](const std::vector<int>& v) {
      |                ^
      |                                              -> __gnu_cxx::__normal_iterator<const int *, std::vector<int>>

https://godbolt.org/z/zzYMa4o5r

It should be suggesting std::vector<int>::const_iterator.