Add script to lint verify

`verify` is intentionally not part of the workspace. Add a script to
lint it.

Author: tcharding

contrib/lint-verify.sh

@@ -0,0 +1,14 @@
+#!/usr/bin/env bash
+#
+# The `verify` crate is not part of the workspace because it is a dev tool.
+
+set -euox pipefail
+
+REPO_DIR=$(git rev-parse --show-toplevel)
+
+cargo +"$(cat ./nightly-version)" clippy \
+      --manifest-path "$REPO_DIR/verify/Cargo.toml" \
+      --config ./rustfmt.toml \
+      --all-targets --all-features \
+      -- --deny warnings
+