[synthetic-monitoring-agent] Update docker.io/grafana/synthetic-monitoring-agent Docker tag to v0.51.2 (#46)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

charts/synthetic-monitoring-agent/Chart.yaml

@@ -1,6 +1,6 @@
 apiVersion: v2
 # renovate: docker=docker.io/grafana/synthetic-monitoring-agent
-appVersion: v0.51.1
+appVersion: v0.51.2
 description: |
   Grafana's Synthetic Monitoring application. The agent provides probe functionality and executes network checks for monitoring remote targets.
 
@@ -20,4 +20,4 @@ name: synthetic-monitoring-agent
 sources:
   - https://github.com/grafana/synthetic-monitoring-agent
 type: application
-version: 1.4.0
+version: 1.4.1