Incorrect renaming between varsym and varid

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
```
