feat: add Dockerfile to parametrically build from alpine

Dockerfile

@@ -0,0 +1,19 @@
+ARG ALPINE_VERSION=edge
+FROM docker.io/alpine:${ALPINE_VERSION}
+
+ARG OPENLDAP_VERSION=2.6.8-r0
+RUN mkdir -p /run/openldap
+RUN apk --no-cache add \
+  "openldap=${OPENLDAP_VERSION}" \
+  openldap-back-mdb \
+  openldap-back-sql \
+  openldap-overlay-dds \
+  openldap-overlay-refint \
+  openldap-overlay-memberof \
+  openldap-overlay-ppolicy \
+  openldap-overlay-auditlog \
+  openldap-overlay-dynlist \
+  openldap-passwd-argon2 \
+  openldap-passwd-pbkdf2
+
+CMD ["/usr/bin/slapd", "-d", "none", "-h", "ldapi://%2fvar%2frun%2fsockets%2fslapd.sock"]