fix(deps): bump alpine from 3.14.2 to 3.15.4 in /alpine (#114)

* fix(deps): bump alpine from 3.14.2 to 3.15.4 in /alpine

Bumps alpine from 3.14.2 to 3.15.4.

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

Signed-off-by: dependabot[bot] <support@github.com>

* fix: Package versions

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Lukas Holota <lholota@vistaprint.com>
Co-authored-by: LH <l.holota@outlook.com>

alpine/Dockerfile

@@ -1,4 +1,4 @@
-FROM alpine:3.14.2
+FROM alpine:3.15.4
 
 LABEL maintainer="Lukas Holota <me@lholota.com>"
 
@@ -14,10 +14,10 @@ RUN tar xzf /tmp/s6-overlay-${CPU_ARCH}.tar.gz -C / && \
     # These packages are included in the base image. They are explicitly upgrade to vulnerabilities below
     apk add --no-cache \
         # CVE-2021-36159
-        apk-tools=2.12.7-r0 \
+        apk-tools=2.12.7-r3 \
         # CVE-2021-3711, CVE-2021-3712
-        libssl1.1=1.1.1l-r0 && \
-    apk add --no-cache shadow=4.8.1-r0 && \
+        libssl1.1=1.1.1n-r0 \
+        shadow=4.8.1-r1 && \
     rm /tmp/s6-overlay-${CPU_ARCH}.tar.gz
 
 COPY ./fs /