Auto merge of #12808 - Veykril:check-workspace, r=Veykril

feat: Only flycheck workspace that belongs to saved file

Supercedes https://github.com/rust-lang/rust-analyzer/pull/11038

There is still the problem that all the diagnostics are cleared, only clearing diagnostics of the relevant workspace isn't easily doable though I think, will have to dig into that

diff --cc crates/flycheck/src/lib.rs
Simple merge

diff --cc crates/paths/src/lib.rs
Simple merge

diff --cc crates/rust-analyzer/src/global_state.rs
Simple merge

diff --cc crates/rust-analyzer/src/handlers.rs
Simple merge

diff --cc crates/rust-analyzer/src/main_loop.rs
Simple merge

diff --cc crates/rust-analyzer/src/reload.rs
Simple merge