This is trying to reduce how much we run tidy over due to poor
performance of tidy.
It's opening the door for issues where a header file is modified in a
way that introduces tidy issues in a different target. However, that's
not the typical tidy issue we see.
There may also be a risk where a source file indirectly becomes a source
file for a target in a way that `same_pkg_direct_rdeps` doesn't return,
but I'm not sure that's applicable for how we use targets.
An example of this locating a diagnostic error can be found in the "Add
tidy issue" commit's run (which I cancelled before it finished running,
but note the error):
https://github.com/carbon-language/carbon-lang/actions/runs/13932649182/job/38993348130?pr=5144
Trying to improve robustness against failures such as
[here](https://github.com/carbon-language/carbon-lang/actions/runs/11845529962/job/33011203628):
```
WARNING: Download from https://ftp.gnu.org/gnu/m4/m4-1.4.18.tar.xz failed: class java.net.ConnectException Connection refused
```
Which is coming from the target-determinator invocation:
```
subprocess.CalledProcessError: Command '['/home/runner/.cache/carbon-lang-scripts/target-determinator', '--bazel=/usr/local/bin/bazelisk', 'a720921dfb99c21f08832663c91a1f9e48a1bcc4']' returned non-zero exit status 1.
```
My thought is that the `bazel cquery` should trigger equivalent
downloads (equally though, I'd thought the `bazel mod deps` would do
that, so I don't want to give the impression of confidence).
It's harder to inject this into the target-determinator command line,
since we'd need something that retries by default.
Because clang-tidy is slow (and I'm not sure we can make it really
fast), trying to run it slightly less. Also, I noticed we can shave a
few minutes by disabling apt removal without losing too much free space.
Note that since this removes the old clang-tidy, I'll need to change the
branch protections before merging.
Jon Ross-Perkins