chore(deps): bump the docker-dependencies group with 1 update

Bumps the docker-dependencies group with 1 update: alpine.


Updates `alpine` from 3.18 to 3.19

---
updated-dependencies:
- dependency-name: alpine
  dependency-type: direct:production
  update-type: version-update:semver-minor
  dependency-group: docker-dependencies
...

Signed-off-by: dependabot[bot] <[email protected]>

Dockerfile

@@ -12,7 +12,7 @@ RUN --mount=type=cache,target=/go/pkg/mod \
     go build -o /go/bin/http-header-authenticator -v ./...
 
 # final stage
-FROM alpine:3.18
+FROM alpine:3.19
 RUN apk --no-cache add ca-certificates
 COPY --from=builder /go/bin/http-header-authenticator /usr/local/bin/http-header-authenticator
 COPY entrypoint.sh /entrypoint.sh