[libcxx][NFC] removes IndentRequires from .clang-format

IndentRequires is apparently breaking CI because it uses an older clang-format.

Partially rolls back 2e3a78b8ca10.

GitOrigin-RevId: 6f3bce911ecfbfb2aa80bad5687ef6e87b7ba01a
diff --git a/.clang-format b/.clang-format
index bdd9ef0..cfa0c28 100644
--- a/.clang-format
+++ b/.clang-format
@@ -13,7 +13,4 @@
 
 # libc++ has some long names so we need more than the 80 column limit imposed by LLVM style, for sensible formatting
 ColumnLimit: 120
-
-# These aren't covered by the LLVM Style Guide
-IndentRequires: false
 ---