Rollup of 16 pull requests

[Centril]

Successful merges:

• improve pinning projection docs #61878 (improve pinning projection docs)
• Remove FnBox #62043 (Remove FnBox)
• Add suggestion for missing .await keyword #62067 (Add suggestion for missing .await keyword)
• Updated RELEASES.md for 1.36.0 #62076 (Updated RELEASES.md for 1.36.0)
• call out explicitly that general read needs to be called with an initialized buffer #62102 (call out explicitly that general read needs to be called with an initialized buffer)
• Add more tests for async/await #62106 (Add more tests for async/await)
• refactor lexer to use idiomatic borrowing #62124 (refactor lexer to use idiomatic borrowing)
• Implement mem::{zeroed,uninitialized} in terms of MaybeUninit. #62150 (Implement mem::{zeroed,uninitialized} in terms of MaybeUninit.)
• Don't ICE on item in .await expression #62152 (Don't ICE on item in .await expression)
• Remove old fixme #62154 (Remove old fixme)
• Add regression test for MIR drop generation in async loops #62155 (Add regression test for MIR drop generation in async loops)
• Update books #62156 (Update books)
• Remove outdated question_mark_macro_sep lint #62160 (Remove outdated question_mark_macro_sep lint)
• save-analysis: use buffered writes #62164 (save-analysis: use buffered writes)
• rustc: Retry SIGILL linker invocations #62171 (rustc: Retry SIGILL linker invocations)
• Update RLS #62176 (Update RLS)

Failed merges:

r? @ghost