Use interned symbols instead of strings in more places (#14840)

This patch series makes heavy use of interned symbols when matching
against known method names:

- the first commit reorders the current list of symbols in
`clippy_utils::sym`
- the second commit adds symbol reordering and order checking to `clippy
dev fmt` / `clippy dev fmt --check`
- the third commit converts many uses of string matching during linting
to symbols matching

The symbols are kept as-is (not rendered as strings) as much as possible
to avoid needing locking the interner as much as possible. Static
strings have been kept when they are only used when emitting a
diagnostic, as there is no benefit in using interned strings for
de-interning them right after.

changelog: none

r? @Alexendoo

0 files changed, 0 insertions, 0 deletions