fix: go back to using root user in Dockerfile (#600)

We have to do this because we have no active way to change
permissions to $GITHUB_OUTPUT to a specific user when
running the container

Add trivy ignore to top of Dockerfile to pass linting

Signed-off-by: jmeridth <jmeridth@gmail.com>

Author: jmeridth

Dockerfile

@@ -1,5 +1,6 @@
 #checkov:skip=CKV_DOCKER_2
 #checkov:skip=CKV_DOCKER_3
+#trivy:ignore:AVD-DS-0002
 FROM python:3.13-slim@sha256:58c30f5bfaa718b5803a53393190b9c68bd517c44c6c94c1b6c8c172bcfad040
 LABEL com.github.actions.name="issue-metrics" \
     com.github.actions.description="Gather metrics on issues/prs/discussions such as time to first response, count of issues opened, closed, etc." \
@@ -18,13 +19,7 @@ COPY requirements.txt *.py /action/workspace/
 RUN python3 -m pip install --no-cache-dir -r requirements.txt \
     && apt-get -y update \
     && apt-get -y install --no-install-recommends git=1:2.47.3-0+deb13u1 \
-    && rm -rf /var/lib/apt/lists/* \
-    && addgroup --system appuser \
-    && adduser --system --ingroup appuser --home /action/workspace --disabled-login appuser \
-    && chown -R appuser:appuser /action/workspace
-
-# Run the action as a non-root user
-USER appuser
+    && rm -rf /var/lib/apt/lists/*
 
 # Add a simple healthcheck to satisfy container scanners
 HEALTHCHECK --interval=30s --timeout=10s --start-period=10s --retries=3 \