Add lit test

Author: snarang181

clang-tools-extra/test/clang-doc/Inputs/html-tag-comment.yaml

@@ -0,0 +1,12 @@
+---
+Name:            'withHtmlTag'
+Description:
+  - Kind:          FullComment
+    Children:
+      - Kind:        VerbatimBlockComment
+        Name:        'verbatim'
+        CloseName:   'endverbatim'
+        Children:
+          - Kind:      VerbatimBlockLineComment
+            Text:      '<ul class="test"><li> Testing. </li></ul>'
+...

clang-tools-extra/test/clang-doc/html-tag-comment.cpp

@@ -0,0 +1,17 @@
+// RUN: clang-doc --public --format=yaml -p %T %s -output=%t
+// RUN: FileCheck --input-file=%S/Inputs/html-tag-comment.yaml %s
+
+/// \verbatim <ul class="test"><li> Testing. </li></ul> \endverbatim
+void withHtmlTag() {}
+// CHECK: ---
+// CHECK: Name:            'withHtmlTag'
+// CHECK: Description:
+// CHECK:   - Kind:          FullComment
+// CHECK:     Children:
+// CHECK:       - Kind:        VerbatimBlockComment
+// CHECK:         Name:        'verbatim'
+// CHECK:         CloseName:   'endverbatim'
+// CHECK:         Children:
+// CHECK:           - Kind:      VerbatimBlockLineComment
+// CHECK:             Text:      '<ul class="test"><li> Testing. </li></ul>'
+// CHECK: ...