chore(deps): update alpine docker tag to v3.21 (#1431)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| alpine | final | minor | `3.20` -> `3.21` |

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Dockerfile

@@ -21,7 +21,7 @@ RUN go mod download
 COPY ./ ./
 RUN go build -o osv-scanner ./cmd/osv-scanner/
 
-FROM alpine:3.20@sha256:1e42bbe2508154c9126d48c2b8a75420c3544343bf86fd041fb7527e017a4b4a
+FROM alpine:3.21@sha256:21dc6063fd678b478f57c0e13f47560d0ea4eeba26dfc947b2a4f81f686b9f45
 
 RUN apk --no-cache add ca-certificates git && \
   git config --global --add safe.directory '*'

action.dockerfile

@@ -25,7 +25,7 @@ COPY ./ /src/
 RUN go build -o osv-scanner ./cmd/osv-scanner/
 RUN go build -o osv-reporter ./cmd/osv-reporter/
 
-FROM alpine:3.20@sha256:1e42bbe2508154c9126d48c2b8a75420c3544343bf86fd041fb7527e017a4b4a
+FROM alpine:3.21@sha256:21dc6063fd678b478f57c0e13f47560d0ea4eeba26dfc947b2a4f81f686b9f45
 RUN apk --no-cache add \
   ca-certificates \
   git \

goreleaser-action.dockerfile

@@ -12,7 +12,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-FROM alpine:3.20@sha256:1e42bbe2508154c9126d48c2b8a75420c3544343bf86fd041fb7527e017a4b4a
+FROM alpine:3.21@sha256:21dc6063fd678b478f57c0e13f47560d0ea4eeba26dfc947b2a4f81f686b9f45
 RUN apk --no-cache add \
   ca-certificates \
   git \

goreleaser.dockerfile

@@ -12,7 +12,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-FROM alpine:3.20@sha256:1e42bbe2508154c9126d48c2b8a75420c3544343bf86fd041fb7527e017a4b4a
+FROM alpine:3.21@sha256:21dc6063fd678b478f57c0e13f47560d0ea4eeba26dfc947b2a4f81f686b9f45
 
 RUN apk add --no-cache \
     ca-certificates \