bazel: Upgrade to 7.4.0, set max disk cache size (#30395)

Upgrades the version of Bazel we use from `7.2.1` to `7.4.0`. Developers
won't need to do anything since we use `bazelisk`, the new version will
automatically get downloaded for them.

This also updates our `.bazelrc` to include:
```
common --experimental_disk_cache_gc_max_size=80G
```
This combined with users specifying `--disk_cache` in their home
`.bazelrc`, should bound the total size of artifacts that are kept
around for builds. Hopefully this should solve the "Low Disk Warnings"
folks frequently run into, if they use Bazel instead of Cargo.

### Motivation

Pickup the new automatic gc disk cache to bound the total size of
artifacts.

### Checklist

- [x] This PR has adequate test coverage / QA involvement has been duly
considered. ([trigger-ci for additional test/nightly
runs](https://trigger-ci.dev.materialize.com/))
- [x] This PR has an associated up-to-date [design
doc](https://github.com/MaterializeInc/materialize/blob/main/doc/developer/design/README.md),
is a design doc
([template](https://github.com/MaterializeInc/materialize/blob/main/doc/developer/design/00000000_template.md)),
or is sufficiently small to not require a design.
  <!-- Reference the design in the description. -->
- [x] If this PR evolves [an existing `$T ⇔ Proto$T`
mapping](https://github.com/MaterializeInc/materialize/blob/main/doc/developer/command-and-response-binary-encoding.md)
(possibly in a backwards-incompatible way), then it is tagged with a
`T-proto` label.
- [x] If this PR will require changes to cloud orchestration or tests,
there is a companion cloud PR to account for those changes that is
tagged with the release-blocker label
([example](MaterializeInc/cloud#5021)).
<!-- Ask in #team-cloud on Slack if you need help preparing the cloud
PR. -->
- [x] If this PR includes major [user-facing behavior
changes](https://github.com/MaterializeInc/materialize/blob/main/doc/developer/guide-changes.md#what-changes-require-a-release-note),
I have pinged the relevant PM to schedule a changelog post.

.bazelrc

@@ -69,6 +69,9 @@ common --experimental_remote_merkle_tree_cache
 common --experimental_remote_merkle_tree_cache_size=5000
 # Don't make the user wait for uploading artifacts to complete, finish it in the background.
 common --bes_upload_mode=fully_async
+# Make sure any local disk cache stays within a reasonable size.
+common --experimental_disk_cache_gc_max_size=80G
+
 # Tells `xz` to use all available cores.
 action_env=XZ_OPT=-T0
 

.bazelversion

@@ -1 +1 @@
-7.2.1
+7.4.0

ci/builder/Dockerfile

@@ -283,8 +283,8 @@ ARG BAZEL_VERSION
 # contain arm64 releases.
 RUN arch_bazel=$(echo "$ARCH_GCC" | sed -e "s/aarch64/arm64/" -e "s/amd64/x86_64/") bazel_version=$(echo "$BAZEL_VERSION") \
     && curl -fsSL -o /usr/local/bin/bazel https://github.com/bazelbuild/bazel/releases/download/$bazel_version/bazel-$bazel_version-linux-$arch_bazel \
-    && if [ "$arch_bazel" = arm64 ]; then echo '5a4cc979353671e438b9469b833924c2361e25a580cc278a75877aedc27c1c53 /usr/local/bin/bazel' | sha256sum --check; fi \
-    && if [ "$arch_bazel" = x86_64 ]; then echo '80ccd1ecb4b88750fbe5d7622d67072fddcba9da7808f13356555e480bf67875 /usr/local/bin/bazel' | sha256sum --check; fi \
+    && if [ "$arch_bazel" = arm64 ]; then echo 'fac4b954e0501c2be8b9653a550b443eb85284e568d08b102977e2bf587b09d7 /usr/local/bin/bazel' | sha256sum --check; fi \
+    && if [ "$arch_bazel" = x86_64 ]; then echo '48ea0ff9d397a48add6369c261c5a4431fe6d5d5348cfb81411782fb80c388d3 /usr/local/bin/bazel' | sha256sum --check; fi \
     && chmod +x /usr/local/bin/bazel
 
 # Hardcode some known SSH hosts, or else SSH will ask whether the host is

misc/bazel/README.md

@@ -95,7 +95,8 @@ Bazel has numerous [command line options](https://bazel.build/reference/command-
 which can be defined in a `.bazelrc` file to create different configurations that you run Bazel
 with. We have a [`.bazelrc`](../../.bazelrc) in the root of our repository that defines several
 common build configurations, but it's also recommended that you create a `.bazelrc` in your home
-directory (i.e. `~/.bazelrc`) to customize how you run Bazel locally.
+directory (i.e. `~/.bazelrc`) to customize how you run Bazel locally. Options specified in your
+home RC file will override those of the workspace RC file.
 
 A good default to start with is:
 ```
@@ -104,6 +105,10 @@ common --local_resources=cpu="HOST_CPUS-1"
 
 # Define a shared disk cache so builds from different Materialize repos can share artifacts.
 build --disk_cache=~/.cache/bazel
+
+# Optional. The workspace RC already sets a max disk cache size, but you can override that if you
+# have more limited disk space.
+common --experimental_disk_cache_gc_max-size=40G
 ```
 
 # How Bazel Works