Bump alpine from 3.13.5 to 3.14.0 (#10)

Bumps alpine from 3.13.5 to 3.14.0.

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

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

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

Dockerfile

@@ -7,7 +7,7 @@ RUN go test ./...
 ARG version=dev
 RUN go build -ldflags "-X main.Version=$version" -o /bin/blackhole
 
-FROM alpine:3.13.5
+FROM alpine:3.14.0
 RUN apk add --no-cache
 
 COPY --from=build /bin/blackhole /usr/local/bin/blackhole