changed the target folder reference in git ignore file;

changed the name of rust.rs to build.rs;
fixed config env variables;
added integration tests lib module;
changed the api project main file to easier the tests;

Author: rogerio-cyclomedia

.gitignore

@@ -1,4 +1,4 @@
-/target
+target
 stderr.log
 .vscode
 setup.toml

rust.rs renamed to build.rs

@@ -17,7 +17,7 @@ pub fn generate_cargo_keys() {
             Cow::from("unknown")
         }
         Err(err) => {
-            println!("cargo:warning=Failed to execute git command: {}", Err);
+            println!("cargo:warning=Failed to execute git command: {}", err);
             Cow::from("unknown")
         }
     };