chore(deps): update golang:1.21-alpine docker digest to 1c9cc94 (#1690)

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This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| golang | stage | digest | `96634e5` -> `1c9cc94` |

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docker/indexer/Dockerfile

@@ -12,7 +12,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-FROM golang:1.21-alpine@sha256:96634e55b363cb93d39f78fb18aa64abc7f96d372c176660d7b8b6118939d97b AS GO_BUILD
+FROM golang:1.21-alpine@sha256:1c9cc949513477766da12bfa80541c4f24957323b0ee00630a6ff4ccf334b75b AS GO_BUILD
 WORKDIR /build
 
 # Cache dependencies in these steps

docker/terraform/Dockerfile

@@ -1,6 +1,6 @@
 # Taken and modified from https://github.com/GoogleCloudPlatform/cloud-builders-community/tree/master/terraform
 
-FROM golang:1.21-alpine@sha256:96634e55b363cb93d39f78fb18aa64abc7f96d372c176660d7b8b6118939d97b AS GO_BUILD
+FROM golang:1.21-alpine@sha256:1c9cc949513477766da12bfa80541c4f24957323b0ee00630a6ff4ccf334b75b AS GO_BUILD
 
 ARG TERRAFORM_VERSION
 WORKDIR /build/