buster: Remove html5validator and openjdk to fix image build

Dockerfile.buster

@@ -3,13 +3,13 @@ FROM debian:buster AS uffd-base
 RUN apt-get -qq update && \
     apt-get -qq dist-upgrade && \
     apt-get -qq install \
-        lsb-release openjdk-11-jre-headless curl ca-certificates \
+        lsb-release curl ca-certificates \
         sqlite3 locales-all git \
         python3 python3-venv python3-coverage python3-ldap3 python3-flask python3-flask-sqlalchemy python3-flask-migrate \
         python3-pip python3-qrcode python3-fido2 python3-oauthlib python3-flask-babel python3-argon2 python3-pytest python3-all python3-pip \
         git-buildpackage debhelper dh-python mariadb-server python3-mysqldb python3-flask-oauthlib python3-requests-oauthlib python3-git \
         python3-prometheus-client libffi-dev redis-server && \
-    pip3 install pylint html5validator twine build --upgrade && \
+    pip3 install pylint twine build --upgrade && \
     apt-get -qq clean
 
 COPY cccv-archive-key.gpg /etc/apt/trusted.gpg.d/