Move string utility file (#4164)

Moves the string file to string.h. This is required since other required utilities will soon need to be added to regexp.h.

1 files changed, 1 insertions, 1 deletions

diff --git a/test/unit/theory/theory_strings_skolem_cache_black.h b/test/unit/theory/theory_strings_skolem_cache_black.h
index 34e8d88c6..e1b84492c 100644
--- a/test/unit/theory/theory_strings_skolem_cache_black.h
+++ b/test/unit/theory/theory_strings_skolem_cache_black.h
@@ -20,7 +20,7 @@
 #include "expr/node_manager.h"
 #include "theory/strings/skolem_cache.h"
 #include "util/rational.h"
-#include "util/regexp.h"
+#include "util/string.h"
 
 using namespace CVC4;
 using namespace CVC4::theory::strings;