Remove PG13 references, add PG18 where needed for component images

Author: tjmoore4

components/image-postgres/Dockerfile.postgres

@@ -18,7 +18,6 @@ set -e
 # see project for compatibility details:
 # https://github.com/pgaudit/pgaudit#postgresql-version-compatibility
 PGAUDIT_PKG="$(case "$POSTGRES_MAJOR_VERSION" in \
-    13) echo pgaudit15_13 ;; \
     14) echo pgaudit16_14 ;; \
     15) echo pgaudit17_15 ;; \
     *)  echo "pgaudit_${POSTGRES_MAJOR_VERSION}" ;; \

components/image-postgres/Dockerfile.postgres-upgrade

@@ -4,7 +4,7 @@
 
 FROM localhost/crunchy-postgres:latest
 
-ARG POSTGRES_UPGRADE_VERSIONS="13 14 15 16 17"
+ARG POSTGRES_UPGRADE_VERSIONS="14 15 16 17 18"
 ARG BASE_VERSION=ubi9
 
 USER 0
@@ -23,7 +23,6 @@ PKGS="$(for POSTGRES_VERSION in ${POSTGRES_UPGRADE_VERSIONS}; do
 POSTGRES_MAJOR_VERSION="${POSTGRES_VERSION%.*}"
 
 case "$POSTGRES_MAJOR_VERSION" in
-    13) PGAUDIT_PKG=pgaudit15_13 ;;
     14) PGAUDIT_PKG=pgaudit16_14 ;;
     15) PGAUDIT_PKG=pgaudit17_15 ;;
     *)  PGAUDIT_PKG="pgaudit_${POSTGRES_MAJOR_VERSION}" ;;