[beta] Rollup backports

[pietroalbini]

Merged and approved:

• NLL: cast causes failure to promote to static  #55385: NLL: cast causes failure to promote to static
• remove "approx env bounds" if we already know from trait #56043: remove "approx env bounds" if we already know from trait
• do not propagate inferred bounds on trait objects if they involve Self #56003: do not propagate inferred bounds on trait objects if they involve Self
• Rewrite ... as ..= as a MachineApplicable 2018 idiom lint #55852: Rewrite ... as ..= as a MachineApplicable 2018 idiom lint
• rustdoc: don't inline pub use some_crate unless directly asked to #55804: rustdoc: don't inline pub use some_crate unless directly asked to
• Increase Duration approximate equal threshold to 1us #56059: Increase Duration approximate equal threshold to 1us

r? @ghost

[pietroalbini]

@bors r+ p=10

[bors]

📌 Commit 4541827 has been approved by pietroalbini

[pietroalbini]

@bors r-

[pietroalbini]

@bors r+ p=10

[bors]

📌 Commit 1d1213f has been approved by pietroalbini

[bors]

⌛ Testing commit 1d1213f with merge ac8413a2bcbab9ad90b3e41c5a281de216de9a74...

[bors]

💔 Test failed - status-appveyor

[kennytm]

Needs to backport a clippy update.

[00:57:55] error[E0050]: method `check_pat` has 3 parameters but the declaration in trait `rustc::lint::EarlyLintPass::check_pat` has 4
[00:57:55]    --> tools\clippy\clippy_lints\src\misc_early.rs:219:57
[00:57:55]     |
[00:57:55] 219 |     fn check_pat(&mut self, cx: &EarlyContext<'_>, pat: &Pat) {
[00:57:55]     |                                                         ^^^^ expected 4 parameters, found 3
[00:57:55]     |
[00:57:55]     = note: `check_pat` from trait: `fn(&mut Self, &rustc::lint::EarlyContext<'_>, &syntax::ast::Pat, &mut bool)`
[00:57:55] 
[00:57:55] error: aborting due to previous error

[nikomatsakis]

I rebased #56102 atop this PR