[MISC] (deps): Bump arm64v8/alpine from 3.12.2 to 3.12.3 (#1571)

Bumps arm64v8/alpine from 3.12.2 to 3.12.3.

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

Co-authored-by: dependabot-preview[bot] <27856297+dependabot-preview[bot]@users.noreply.github.com>

Co-authored-by: James Elliott <james-d-elliott@users.noreply.github.com>

Dockerfile.arm64v8

@@ -52,7 +52,7 @@ GOOS=linux GOARCH=arm64 CGO_ENABLED=1 CC=aarch64-linux-musl-gcc go build -tags n
 # ===================================
 # ===== Authelia official image =====
 # ===================================
-FROM arm64v8/alpine:3.12.2
+FROM arm64v8/alpine:3.12.3
 
 WORKDIR /app