chore(deps): update golang:alpine docker digest to 7839c9f (#444)

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This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| golang | stage | digest | `fd9d9d7` -> `7839c9f` |

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Dockerfile

@@ -12,7 +12,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-FROM golang:alpine@sha256:fd9d9d7194ec40a9a6ae89fcaef3e47c47de7746dd5848ab5343695dbbd09f8c AS builder
+FROM golang:alpine@sha256:7839c9f01b5502d7cb5198b2c032857023424470b3e31ae46a8261ffca72912a AS builder
 
 WORKDIR /src
 COPY ./go.mod ./go.sum ./