feat(Tests): Added unit tests for strung

src/string.rs

@@ -1,3 +1,6 @@
 mod my_str_strict;
 
 pub use my_str_strict::Str;
+
+#[cfg(test)]
+mod tests;

src/string/tests.rs

@@ -0,0 +1,6 @@
+use super::Str;
+
+#[test]
+fn createdsucsessfuly() {
+    let _s: Str = Str::new();
+}