Fix find_only_token_in_range with expression parentheses (#5645)

## Summary

Fix an oversight in `find_only_token_in_range` where the following code
would panic due do the closing and opening parentheses being in the
range we scan:
```python
d1 = [
    ("a") if # 1
    ("b") else # 2
    ("c")
]
```
Closing and opening parentheses respectively are now correctly skipped.

## Test Plan

I added a regression test

crates/ruff_python_formatter/tests/snapshots/format@expression__if.py.snap

@@ -37,6 +37,14 @@ c2 = (
     # 8
     "b" # 9
 )
+
+# regression test: parentheses outside the expression ranges interfering with finding
+# the `if` and `else` token finding
+d1 = [
+    ("a") if # 1
+    ("b") else # 2
+    ("c")
+]
 ```
 
 ## Output
@@ -78,6 +86,16 @@ c2 = (
     # 8
     else "b"  # 9
 )
+
+# regression test: parentheses outside the expression ranges interfering with finding
+# the `if` and `else` token finding
+d1 = [
+    ("a")
+    # 1
+    if ("b")
+    # 2
+    else ("c")
+]
 ```