Revert "Fix modernize-raw-string-literal complaints from clang-tidy."

This reverts commit 7a34bd7c28.

Broke windows build. Can apparently fix with /Zc:preprocessor flag
for windows but need a Windows dev to make that fix.

source/blender/blenlib/tests/BLI_string_test.cc

@@ -845,12 +845,12 @@ TEST_F(StringEscape, Simple)
       {"\\A", "\\\\A"},
       {"A\\B", "A\\\\B"},
       {"?", "?"},
-      {R"("\)", R"(\"\\)"},
-      {R"(\")", R"(\\\")"},
-      {R"("\")", R"(\"\\\")"},
+      {"\"\\", "\\\"\\\\"},
+      {"\\\"", "\\\\\\\""},
+      {"\"\\\"", "\\\"\\\\\\\""},
 
-      {R"(""")", R"(\"\"\")"},
-      {R"(\\\)", R"(\\\\\\)"},
+      {"\"\"\"", "\\\"\\\"\\\""},
+      {"\\\\\\", "\\\\\\\\\\\\"},
   };
 
   testEscapeWords(equal);
@@ -868,9 +868,9 @@ TEST_F(StringEscape, Control)
       {"\f", "\\f"},
       {"A\n", "A\\n"},
       {"\nA", "\\nA"},
-      {"\n\r\t\a\b\f", R"(\n\r\t\a\b\f)"},
-      {"\n_\r_\t_\a_\b_\f", R"(\n_\r_\t_\a_\b_\f)"},
-      {"\n\\\r\\\t\\\a\\\b\\\f", R"(\n\\\r\\\t\\\a\\\b\\\f)"},
+      {"\n\r\t\a\b\f", "\\n\\r\\t\\a\\b\\f"},
+      {"\n_\r_\t_\a_\b_\f", "\\n_\\r_\\t_\\a_\\b_\\f"},
+      {"\n\\\r\\\t\\\a\\\b\\\f", "\\n\\\\\\r\\\\\\t\\\\\\a\\\\\\b\\\\\\f"},
   };
 
   testEscapeWords(escaped);