chore(deps): update dock.mau.dev/mautrix/slack docker tag to v0.2603.0

roles/custom/matrix-bridge-mautrix-slack/defaults/main.yml

@@ -17,7 +17,7 @@ matrix_mautrix_slack_container_image_self_build_repo: "https://mau.dev/mautrix/s
 matrix_mautrix_slack_container_image_self_build_branch: "{{ 'main' if matrix_mautrix_slack_version == 'latest' else matrix_mautrix_slack_version }}"
 
 # renovate: datasource=docker depName=dock.mau.dev/mautrix/slack
-matrix_mautrix_slack_version: v0.2602.0
+matrix_mautrix_slack_version: v0.2603.0
 # See: https://mau.dev/mautrix/slack/container_registry
 matrix_mautrix_slack_container_image: "{{ matrix_mautrix_slack_container_image_registry_prefix }}mautrix/slack:{{ matrix_mautrix_slack_version }}"
 matrix_mautrix_slack_container_image_registry_prefix: "{{ 'localhost/' if matrix_mautrix_slack_container_image_self_build else matrix_mautrix_slack_container_image_registry_prefix_upstream }}"