build: fix clippy warning

Author: pietroalbini

src/build.rs

@@ -156,7 +156,7 @@ impl BuildDirectory {
         let res = f(&Build {
             dir: self,
             toolchain,
-            sandbox: sandbox.clone(),
+            sandbox,
         })?;
 
         remove_dir_all(&source_dir)?;

tests/buildtest/inside_docker.rs

@@ -80,9 +80,9 @@ impl CommandExt for Command {
         if !out.status.success() {
             eprintln!("failed to execute command {:?}", self);
             eprintln!("stdout:");
-            std::io::stderr().lock().write(&out.stdout)?;
+            std::io::stderr().lock().write_all(&out.stdout)?;
             eprintln!("stderr:");
-            std::io::stderr().lock().write(&out.stderr)?;
+            std::io::stderr().lock().write_all(&out.stderr)?;
             failure::bail!("failed to execute command {:?}", self);
         }
         Ok(())

tests/integration/crates_git.rs

@@ -37,7 +37,7 @@ fn test_fetch() -> Result<(), Error> {
 
     // Make a new commit
     repo.commit(&workspace)?;
-    let new_commit = repo.last_commit_sha.clone().unwrap();
+    let new_commit = repo.last_commit_sha.unwrap();
     assert_ne!(initial_commit, new_commit);
     assert_eq!(initial_commit, krate.git_commit(&workspace).unwrap());
     assert_eq!(initial_commit, cloned_commit()?);