Address clippy complaints in libclarity.rs

Signed-off-by: Jacinta Ferrant <[email protected]>

Author: jferrant

clarity/src/libclarity.rs

@@ -101,9 +101,9 @@ const GIT_COMMIT: Option<&'static str> = option_env!("GIT_COMMIT");
 const GIT_TREE_CLEAN: Option<&'static str> = option_env!("GIT_TREE_CLEAN");
 
 #[cfg(debug_assertions)]
-const BUILD_TYPE: &'static str = "debug";
+const BUILD_TYPE: &str = "debug";
 #[cfg(not(debug_assertions))]
-const BUILD_TYPE: &'static str = "release";
+const BUILD_TYPE: &str = "release";
 
 pub fn version_string(pkg_name: &str, pkg_version: &str) -> String {
     let git_branch = GIT_BRANCH.unwrap_or("");