[libclang/python] Fix numResults field type of CCRStructure (#158598)

Fix the type of the `numResults` field of `CCRStructure`, as pointed out
here:
llvm/llvm-project#140539 (comment)

Author: DeinAlptraum

clang/bindings/python/clang/cindex.py

@@ -3150,7 +3150,7 @@ def string(self) -> CompletionString:
 
 
 class CCRStructure(Structure):
-    _fields_ = [("results", POINTER(CodeCompletionResult)), ("numResults", c_int)]
+    _fields_ = [("results", POINTER(CodeCompletionResult)), ("numResults", c_uint)]
 
     results: NoSliceSequence[CodeCompletionResult]
     numResults: int