It seems that grcov can't work with cxx bridge

[MochiXu]

My rust project is a FFI library for cpp, it integrates with cxx library.
When generate coverage report, errors happened.

❯ grcov . -s . --binary-path ./target/debug/ -t cobertura --branch --ignore-not-existing -o .                       
03:57:01 [ERROR] A panic occurred at /home/mochix/.cargo/registry/src/rsproxy.cn-8f6827c7555bfaf8/grcov-0.8.19/src/llvm_tools.rs:110: 
Failed to open directory '"./target/debug/"': File system loop found: ./target/debug/build/tantivy_search-125cdd8efd245d38/out/cxxbridge/crate/tantivy_search/build/cargo/build/x86_64-unknown-linux-gnu/relwithdebinfo/build/tantivy_search-eef39e5ef494680d/out/cxxbridge/crate/tantivy_search points to an ancestor ./target/debug/build/tantivy_search-125cdd8efd245d38/out/cxxbridge/crate/tantivy_search

[MochiXu]

This does nod work even with the ignore field added

❯ grcov . -s . --binary-path ./target/debug/ -t cobertura --branch --ignore "./target/debug/build/tantivy_search-125cdd8efd245d38/out/cxxbridge/" -o .          
04:48:52 [ERROR] A panic occurred at /home/mochix/.cargo/registry/src/rsproxy.cn-8f6827c7555bfaf8/grcov-0.8.19/src/llvm_tools.rs:110: 
Failed to open directory '"./target/debug/"': File system loop found: ./target/debug/build/tantivy_search-125cdd8efd245d38/out/cxxbridge/crate/tantivy_search/build/cargo/build/x86_64-unknown-linux-gnu/relwithdebinfo/build/tantivy_search-eef39e5ef494680d/out/cxxbridge/crate/tantivy_search points to an ancestor ./target/debug/build/tantivy_search-125cdd8efd245d38/out/cxxbridge/crate/tantivy_search