build(deps): bump alpine from 3.14.3 to 3.15.0

Bumps alpine from 3.14.3 to 3.15.0.

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

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

Dockerfile

@@ -20,7 +20,7 @@ COPY . .
 
 RUN make release-binary
 
-FROM alpine:3.14.3 AS gomplate
+FROM alpine:3.15.0 AS gomplate
 
 ARG TARGETOS
 ARG TARGETARCH
@@ -33,7 +33,7 @@ RUN wget -O /usr/local/bin/gomplate \
   && chmod +x /usr/local/bin/gomplate
 
 
-FROM alpine:3.14.3
+FROM alpine:3.15.0
 
 # Dex connectors, such as GitHub and Google logins require root certificates.
 # Proper installations should manage those certificates, but it's a bad user