Bump Bazelisk version in container to 1.19.0

Nothing currently wrong with the old bazelisk version, but we're two
minor versions out of date at this point and there's no real point in
not updating.

Dockerfile

@@ -1,6 +1,6 @@
 FROM ubuntu:22.04
 RUN apt-get update && apt-get install -y clang python3 python3-pip git curl
-ARG bazelisk_version=1.17.0
+ARG bazelisk_version=1.19.0
 RUN curl -L https://github.com/bazelbuild/bazelisk/releases/download/v${bazelisk_version}/bazelisk-linux-amd64 > /usr/bin/bazelisk && chmod +x /usr/bin/bazelisk && ln -s /usr/bin/bazelisk /usr/bin/bazel
 WORKDIR /gematria
 COPY . .