Fix makefile to older version

Author: ChakshuGautam

Makefile

@@ -6,7 +6,7 @@ PG_VER=pg15
 PG_VER_NUMBER=$(shell echo $(PG_VER) | cut -c3-)
 TS_VERSION=main
 PREV_TS_VERSION=$(shell wget --quiet -O - https://raw.githubusercontent.com/timescale/timescaledb/${TS_VERSION}/version.config | grep update_from_version | sed -e 's!update_from_version = !!')
-PREV_TS_IMAGE="samagragovernance/postgres:$(PREV_TS_VERSION)-pg$(PG_VER_NUMBER)$(PREV_EXTRA)"
+PREV_TS_IMAGE="timescale/timescaledb:$(PREV_TS_VERSION)-pg$(PG_VER_NUMBER)$(PREV_EXTRA)"
 PREV_IMAGE=$(shell if docker pull $(PREV_TS_IMAGE) >/dev/null; then echo "$(PREV_TS_IMAGE)"; else echo "postgres:$(PG_VER_NUMBER)-alpine"; fi )
 # Beta releases should not be tagged as latest, so BETA is used to track.
 BETA=$(findstring rc,$(TS_VERSION))