Apply nightly clippy lints (#9654)

# Description
- A new one is the removal of unnecessary `#` in raw strings without `"`
inside.
-
https://rust-lang.github.io/rust-clippy/master/index.html#/needless_raw_string_hashes
- The automatically applied removal of `.into_iter()` touched several
places where #9648 will change to the use of the record API. If
necessary I can remove them @IanManske to avoid churn with this PR.
- Manually applied `.try_fold` in two places
- Removed a dead `if`
- Manual: Combat rightward-drift with early return

crates/nu-command/src/platform/ansi/ansi_.rs

@@ -515,12 +515,12 @@ impl Command for AnsiCommand {
             )
             .switch(
                 "escape", // \x1b[
-                r#"escape sequence without the escape character(s) ('\x1b[' is not required)"#,
+                r"escape sequence without the escape character(s) ('\x1b[' is not required)",
                 Some('e'),
             )
             .switch(
                 "osc", // \x1b]
-                r#"operating system command (osc) escape sequence without the escape character(s) ('\x1b]' is not required)"#,
+                r"operating system command (osc) escape sequence without the escape character(s) ('\x1b]' is not required)",
                 Some('o'),
             )
             .switch("list", "list available ansi code names", Some('l'))