Increment Windows cache URL (#6321)

We've seen a series of failures of the form
```
ERROR: D:/a/1/s/daml-assistant/integration-tests/BUILD.bazel:162:1: output 'daml-assistant/integration-tests/create-daml-app-tests.exe' was not created
ERROR: D:/a/1/s/daml-assistant/integration-tests/BUILD.bazel:162:1: not all outputs were created or valid
```
across multiple machines. We suspect cache poisoning as the cause. This
increments the cache URL to effectively clear the cache.

changelog_begin
changelog_end

Co-authored-by: Andreas Herrmann <andreas.herrmann@tweag.io>

build.ps1

@@ -49,6 +49,8 @@ function bazel() {
 # which is a workaround for this problem.
 bazel shutdown
 
+bazel clean --expunge
+
 # Prefetch nodejs_dev_env to avoid permission denied errors on external/nodejs_dev_env/nodejs_dev_env/node.exe
 # It isn’t clear where exactly those errors are coming from.
 bazel fetch @nodejs_dev_env//...

ci/configure-bazel.sh

@@ -74,7 +74,7 @@ if is_windows; then
   SUFFIX="${SUFFIX:0:3}"
   echo "Platform suffix: $SUFFIX"
   # We include an extra version at the end that we can bump manually.
-  CACHE_SUFFIX="$SUFFIX-v2"
+  CACHE_SUFFIX="$SUFFIX-v3"
   CACHE_URL="$CACHE_URL/$CACHE_SUFFIX"
   echo "build:windows-ci --remote_http_cache=https://bazel-cache.da-ext.net/$CACHE_SUFFIX" >> .bazelrc.local
 fi

compatibility/build-release-artifacts-windows.ps1

@@ -37,6 +37,7 @@ function bazel() {
 
 
 bazel shutdown
+bazel clean --expunge
 bazel fetch @nodejs_dev_env//...
 bazel build `
   `-`-experimental_execution_log_file ${ARTIFACT_DIRS}/build_execution_windows.log `

compatibility/test-windows.ps1

@@ -45,6 +45,7 @@ cd compatibility
 cp ../.bazelrc .bazelrc
 
 bazel shutdown
+bazel clean --expunge
 bazel fetch @nodejs_dev_env//...
 bazel build //...
 bazel shutdown