Update s3 storage provider version to 1.6.0, add renovate

Author: Benjamin Blacher

roles/custom/matrix-synapse/defaults/main.yml

@@ -1471,7 +1471,8 @@ matrix_synapse_ext_encryption_config_yaml: |
 # Installing it requires building a customized Docker image for Synapse (see `matrix_synapse_container_image_customizations_enabled`).
 # Enabling this will enable customizations and inject the appropriate Dockerfile clauses for installing synapse-s3-storage-provider.
 matrix_synapse_ext_synapse_s3_storage_provider_enabled: false
-matrix_synapse_ext_synapse_s3_storage_provider_version: 1.5.0
+# renovate: datasource=github-releases packageName=matrix-org/synapse-s3-storage-provider
+matrix_synapse_ext_synapse_s3_storage_provider_version: 1.6.0
 # Controls whether media from this (local) server is stored in s3-storage-provider
 matrix_synapse_ext_synapse_s3_storage_provider_store_local: true
 # Controls whether media from remote servers is stored in s3-storage-provider