## Summary

This PR brings back the functionality to remove empty strings when
converting to an f-string in `UP032`.

For context, #8712 added this
functionality to remove _trailing_ empty strings but it got removed in
#8697 possibly unexpectedly so.

There's one difference which is that this PR will remove _any_ empty
strings and not just trailing ones. For example,

```diff
--- /Users/dhruv/playground/ruff/src/UP032.py
+++ /Users/dhruv/playground/ruff/src/UP032.py
@@ -1,7 +1,5 @@
 (
-    "{a}"
-    ""
-    "{b}"
-    ""
-).format(a=1, b=1)
+    f"{1}"
+    f"{1}"
+)
```

## Test Plan

Run `cargo insta test` and update the snapshots.