Remove static lifetime

const str types do not need an explicit lifetime, remove it. Found by
clippy.

src/wallet/tx_builder.rs

@@ -629,7 +629,7 @@ impl ChangeSpendPolicy {
 
 #[cfg(test)]
 mod test {
-    const ORDERING_TEST_TX: &'static str = "0200000003c26f3eb7932f7acddc5ddd26602b77e7516079b03090a16e2c2f54\
+    const ORDERING_TEST_TX: &str = "0200000003c26f3eb7932f7acddc5ddd26602b77e7516079b03090a16e2c2f54\
                                             85d1fd600f0100000000ffffffffc26f3eb7932f7acddc5ddd26602b77e75160\
                                             79b03090a16e2c2f5485d1fd600f0000000000ffffffff571fb3e02278217852\
                                             dd5d299947e2b7354a639adc32ec1fa7b82cfb5dec530e0500000000ffffffff\