sqlx-cli fails to build on 0.7-dev branch

[joehillen]

Bug Description

The build fails forsqlx-cli on the 0.7-dev branch. It looks like GItHub Actions is not configured to run on this branch, so that's probably why this was missed.

   Compiling sqlx-core v0.6.2 (/home/joe/src/sqlx/sqlx-core)
warning: unused import: `std::ops::DerefMut`
  --> sqlx-core/src/pool/mod.rs:77:5
   |
77 | use std::ops::DerefMut;
   |     ^^^^^^^^^^^^^^^^^^
   |
   = note: `#[warn(unused_imports)]` on by default

error: non-binding let on a synchronization lock
  --> sqlx-core/src/sqlite/statement/unlock_notify.rs:51:13
   |
51 |           let _ = self
   |  _____________^___^
   | |             |
   | |             this lock is not assigned to a binding and is immediately dropped
52 | |             .condvar
53 | |             .wait_while(self.mutex.lock().unwrap(), |fired| !*fired)
54 | |             .unwrap();
   | |_____________________^ this binding will immediately drop the value assigned to it
   |
   = note: `#[deny(let_underscore_lock)]` on by default
help: consider binding to an unused variable to avoid immediately dropping the value
   |
51 |         let _unused = self
   |             ~~~~~~~
help: consider immediately dropping the value
   |
51 ~         drop(self
52 |             .condvar
53 |             .wait_while(self.mutex.lock().unwrap(), |fired| !*fired)
54 ~             .unwrap());
   |

warning: `sqlx-core` (lib) generated 1 warning
error: could not compile `sqlx-core` due to previous error; 1 warning emitted
warning: build failed, waiting for other jobs to finish...
warning: `sqlx-core` (lib) generated 1 warning (1 duplicate)
error: could not compile `sqlx-core` due to previous error; 1 warning emitted

Interestingly cargo build -F runtime-* works fine on this branch. It's just the CLI that fails.

Minimal Reproduction

1. Fresh clone
2. git checkout 0.7-dev
3. cargo build --manifest-path sqlx-cli/Cargo.toml --bin cargo-sqlx

Info

• SQLx version: 4b70538
• SQLx features enabled: defaults, but I tried several and they made no difference
• Database server and version: SQLite 3.39.4
• Operating system: Archlinux
• rustc --version: rustc 1.65.0 (897e37553 2022-11-02)

[abonander]

I believe this has been fixed.