ci: Add missing errexit to lint CI install

Otherwise, a possible failure is silently ignored.

Also, rename the file, while touching it, to clarify installing is the
first step.

ci/lint/01_install.sh

@@ -6,6 +6,8 @@
 
 export LC_ALL=C
 
+set -o errexit -o pipefail -o xtrace
+
 export CI_RETRY_EXE="/ci_retry --"
 
 pushd "/"

ci/lint_imagefile

@@ -12,7 +12,7 @@ ENV LC_ALL=C.UTF-8
 COPY ./ci/retry/retry /ci_retry
 COPY ./.python-version /.python-version
 COPY ./ci/lint/container-entrypoint.sh /entrypoint.sh
-COPY ./ci/lint/04_install.sh /install.sh
+COPY ./ci/lint/01_install.sh /install.sh
 
 RUN /install.sh && \
   echo 'alias lint="./ci/lint/06_script.sh"' >> ~/.bashrc && \

ci/lint_run_all.sh

@@ -13,6 +13,6 @@ cp "./ci/retry/retry" "/ci_retry"
 cp "./.python-version" "/.python-version"
 mkdir --parents "/test/lint"
 cp --recursive "./test/lint/test_runner" "/test/lint/"
-set -o errexit; source ./ci/lint/04_install.sh
+set -o errexit; source ./ci/lint/01_install.sh
 set -o errexit
 ./ci/lint/06_script.sh

test/lint/README.md

@@ -54,7 +54,7 @@ or `--help`:
 | `py_lint` | [ruff](https://github.com/astral-sh/ruff)
 | markdown link check | [mlc](https://github.com/becheran/mlc)
 
-In use versions and install instructions are available in the [CI setup](../../ci/lint/04_install.sh).
+In use versions and install instructions are available in the [CI setup](../../ci/lint/01_install.sh).
 
 Please be aware that on Linux distributions all dependencies are usually available as packages, but could be outdated.