[lldb] Standardize TestVectorOfEnums.py as a C++ data formatter test (#189757)

This is explicitly marked as a libc++ test and functionally tests the
formatter for a vector of enums. I put it in the generic directory
because there's no reason this couldn't work for other c++ stdlibs.

Additionally, this should be using the custom libc++ like the other
tests.

lldb/test/API/functionalities/data-formatter/data-formatter-stl/generic/vector_of_enums/TestVectorOfEnums.py

@@ -3,7 +3,6 @@ Test Expression Parser regression test to ensure that we handle enums
 correctly, in this case specifically std::vector of enums.
 """
 
-
 import lldb
 from lldbsuite.test.decorators import *
 from lldbsuite.test.lldbtest import *
@@ -11,9 +10,11 @@ from lldbsuite.test import lldbutil
 
 
 class TestVectorOfEnums(TestBase):
+    SHARED_BUILD_TESTCASE = False
+
     @add_test_categories(["libc++"])
     def test_vector_of_enums(self):
-        self.build()
+        self.build(dictionary={"USE_LIBCPP": 1})
 
         lldbutil.run_to_source_breakpoint(
             self, "// break here", lldb.SBFileSpec("main.cpp", False)

lldb/test/API/functionalities/data-formatter/data-formatter-stl/generic/vector_of_enums/main.cpp

@@ -1,11 +1,6 @@
 #include <vector>
 
-enum E {
-a,
-b,
-c,
-d
-} ;
+enum E { a, b, c, d };
 
 int main() {
   std::vector<E> v = {E::a, E::b, E::c};