Merge rust-bitcoin/rust-bitcoin#4084: documentation: update instructions for building lock files

948647a9dd update documentation for changing lockfiles; change script to support mac nanaive cp function (jeremiah)

Pull request description:

  1. Updates `CONTRIBUTING.md` with latest instructions on using `just` to create new lock files. See discussion [here](https://github.com/rust-bitcoin/rust-bitcoin/pull/4045/files).
  2. For the command `cp`,  `--force` is not an option on the Mac. Changed to `-f` which as far as I can tell is equivalent.

  ```
  ➜  rust-bitcoin git:(jr_update_contrib) ✗ cp --force
  cp: illegal option -- -
  ```

ACKs for top commit:
  tcharding:
    ACK 948647a9dd
  Kixunil:
    ACK 948647a9dd
  apoelstra:
    ACK 948647a9dd95bedbb8c34f0b9548e859bfc723b1; successfully ran local tests

Tree-SHA512: a9486ec323b15a9cfa78cd70332e153881537ec8fd26e6e23f8b61ed2272251271299723e9aa390542044588357ec072eb1559cd5e32cb707757f58361a6fb05

CONTRIBUTING.md

@@ -209,12 +209,9 @@ in Bitcoin Core, with the following exceptions:
 If your change requires a dependency to be upgraded you must do the following:
 
 1. Modify `Cargo.toml`
-2. Copy `Cargo-minimal.lock` to `Cargo.lock`
-3. Trigger cargo to update the required entries in the lock file - use `--precise` using the minimum version number that works
-4. Test your change
-5. Copy `Cargo.lock` to `Cargo-minimal.lock`
-6. Update `Cargo-recent.lock` if it is also behind
-7. Commit both lock files together with `Cargo.toml` and your code changes
+2. Run `just update-lock-files`, if necessary install `just` first with `cargo install just`.
+3. Test your change
+4. Commit both `Cargo-minimal.lock` and `Cargo-recent.lock` together with `Cargo.toml` and your code changes
 
 ### Unsafe code
 

contrib/update-lock-files.sh

@@ -5,7 +5,7 @@
 set -euo pipefail
 
 for file in Cargo-minimal.lock Cargo-recent.lock; do
-    cp --force "$file" Cargo.lock
+    cp -f "$file" Cargo.lock
     cargo check
-    cp --force Cargo.lock "$file"
+    cp -f Cargo.lock "$file"
 done