Wrap some really long lines.

These do not wrap due to rust-lang/rustfmt#3863.

tests/testsuite/install.rs

@@ -1131,12 +1131,20 @@ and will continue to do so, but this behavior will be removed eventually
 
 #[cargo_test]
 fn test_install_git_cannot_be_a_base_url() {
-    cargo_process("install --git github.com:rust-lang-nursery/rustfmt.git").with_status(101).with_stderr("error: invalid url `github.com:rust-lang-nursery/rustfmt.git`: cannot-be-a-base-URLs are not supported").run();
+    cargo_process("install --git github.com:rust-lang-nursery/rustfmt.git")
+        .with_status(101)
+        .with_stderr("\
+[ERROR] invalid url `github.com:rust-lang-nursery/rustfmt.git`: cannot-be-a-base-URLs are not supported")
+        .run();
 }
 
 #[cargo_test]
 fn uninstall_multiple_and_specifying_bin() {
-    cargo_process("uninstall foo bar --bin baz").with_status(101).with_stderr("error: A binary can only be associated with a single installed package, specifying multiple specs with --bin is redundant.").run();
+    cargo_process("uninstall foo bar --bin baz")
+        .with_status(101)
+        .with_stderr("\
+[ERROR] A binary can only be associated with a single installed package, specifying multiple specs with --bin is redundant.")
+        .run();
 }
 
 #[cargo_test]