build(deps): bump golang in /Containers/watchtower

Bumps golang from 1.24.2-alpine3.21 to 1.24.3-alpine3.21.

---
updated-dependencies:
- dependency-name: golang
  dependency-version: 1.24.3-alpine3.21
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

Containers/watchtower/Dockerfile

@@ -1,5 +1,5 @@
 # syntax=docker/dockerfile:latest
-FROM golang:1.24.2-alpine3.21 AS go
+FROM golang:1.24.3-alpine3.21 AS go
 
 RUN set -ex; \
     apk upgrade --no-cache -a; \