fix timescaledb being picked up from apt

We want timescaledb packages from dedicated repo, where we have all versions

install_pg_extensions.sh

@@ -6,14 +6,7 @@ set -euxo pipefail
 # install extensions
 EXTENSIONS="$@"
 # cycle through extensions list
-for EXTENSION in ${EXTENSIONS}; do
-    # is it an extension found in apt?
-    if apt-cache show "postgresql-${PG_MAJOR}-${EXTENSION}" &> /dev/null; then
-        # install the extension
-        apt-get install -y "postgresql-${PG_MAJOR}-${EXTENSION}"
-        continue
-    fi
-
+for EXTENSION in ${EXTENSIONS}; do    
     # special case: timescaledb
     if [ "$EXTENSION" == "timescaledb" ]; then
         # dependencies
@@ -41,6 +34,13 @@ for EXTENSION in ${EXTENSIONS}; do
         continue
     fi
 
+    # is it an extension found in apt?
+    if apt-cache show "postgresql-${PG_MAJOR}-${EXTENSION}" &> /dev/null; then
+        # install the extension
+        apt-get install -y "postgresql-${PG_MAJOR}-${EXTENSION}"
+        continue
+    fi
+
     # extension not found/supported
     echo "Extension '${EXTENSION}' not found/supported"
     exit 1