[libc++][NFC] Reindent release notes bullet points

NOKEYCHECK=True
GitOrigin-RevId: 197737b539add21fa62b04b964fe69fafdf21feb
diff --git a/docs/ReleaseNotes.rst b/docs/ReleaseNotes.rst
index ce35d57..bc3251e 100644
--- a/docs/ReleaseNotes.rst
+++ b/docs/ReleaseNotes.rst
@@ -38,13 +38,13 @@
 New Features
 ------------
 
- - Implemented P0627R6 (Function to mark unreachable code)
+- Implemented P0627R6 (Function to mark unreachable code)
 
- - Implemented P1165R1 (Make stateful allocator propagation more consistent for ``operator+(basic_string)``)
+- Implemented P1165R1 (Make stateful allocator propagation more consistent for ``operator+(basic_string)``)
 
- - `pop_heap` now uses an algorithm known as "bottom-up heapsort" or
-   "heapsort with bounce" to reduce the number of comparisons, and rearranges
-   elements using move-assignment instead of `swap`.
+- `pop_heap` now uses an algorithm known as "bottom-up heapsort" or
+  "heapsort with bounce" to reduce the number of comparisons, and rearranges
+  elements using move-assignment instead of `swap`.
 
 API Changes
 -----------