Incorrect renaming between varsym and varid

[aavogt]

With hls 1.8 from ghcup:

fun a b = a `fun` b
(&) a b = a `(&)` b   -- renamed fun to (&)
& a b = a `&` b       -- renamed fun to &
(&) a b = a & b -- desired output from either renaming

Going the other way also produces syntax errors:

(&) a b = a & b
(fun) a b = a fun b -- renamed & to fun
fun a b = a `fun` b -- desired output

[michaelpj]

cc @OliverMadine