Update psmdb_setup.sh (#757)

Fix mongosh version 8.0 to use 7.0 for now

pmm-tests/psmdb_setup.sh

@@ -56,8 +56,12 @@ mv ${extracted_folder_name} psmdb_${mongodb_version}
 # TODO: refactor if to match range of versions 6.0+
 if [[ "$mongodb_version" == "6.0" || "$mongodb_version" == "7.0" || "$mongodb_version" == "8.0" ]]; then
 ### PSMDB 6+ requires "percona-mongodb-mongosh" additionally
-    echo "Downloading mongosh ..."
+    if [[ "$mongodb_version" == "8.0" ]]; then
+      # Use Mongo 7.0 mongosh itself for 8.0
+      psmdb_latest=$(wget -q --post-data "version=percona-server-mongodb-7.0" https://www.percona.com/products-api.php -O - | grep  -oP "(?<=value\=\")[^\"]*" | sort -V | tail -1)
+    fi
     mongosh_link=$(wget -q --post-data "version_files=${psmdb_latest}&software_files=binary" https://www.percona.com/products-api.php -O - | jq -r '.[] | select(.link | contains("sha") | not) | .link' | grep mongosh)
+    echo "Downloading mongosh ${mongosh_link}..."
     wget -O mongosh.tar.gz ${mongosh_link}
     tar -xvf mongosh.tar.gz
     mv percona-mongodb-mongosh* mongosh