Added operator= integer operator.

MString.cpp

@@ -139,7 +139,15 @@ namespace coreutils {
       cursor = this->data;
       return *this;
    }
-   
+
+   MString &MString::operator=(int value) {
+      std::string temp = std::format("{}", value);
+      setSize(temp.length());
+      memcpy(this->data, (char *)temp.data(), temp.length());
+      cursor = this->data;
+      return *this;
+   }
+
    MString &MString::operator<<(const char *value) {
       int temp = length;
       int len = strlen(value);