upgrade alpine base image to v3.15.0 including upgrade of postfix package to v3.6.3-r1 and ca-certificates package (see below)

https://git.alpinelinux.org/aports/commit/main/postfix?h=3.15-stable&id=e1771647dd66e51c32fba9a80d5e022fffc9d5ad

https://git.alpinelinux.org/aports/commit/main/ca-certificates?h=3.15-stable&id=f3d3b2d920bafb894bdc14abfcc3b381685c8615
https://git.alpinelinux.org/aports/commit/main/ca-certificates?h=3.15-stable&id=670bf5a8cc5bc605eede8ca2fd55b50a5c9f8660

Dockerfile

@@ -1,9 +1,9 @@
-FROM alpine:3.14.3
+FROM alpine:3.15.0
 
-ARG POSTFIX_PACKAGE_VERSION=3.6.3-r0
+ARG POSTFIX_PACKAGE_VERSION=3.6.3-r1
 # http://www.postfix.org/postconf.5.html#tls_append_default_CA
 # https://www.mozilla.org/en-US/about/governance/policies/security-group/certs/
-ARG MOZILLA_CA_CERT_STORE_PACKAGE_VERSION=20191127-r5
+ARG MOZILLA_CA_CERT_STORE_PACKAGE_VERSION=20191127-r7
 RUN apk add --no-cache \
         ca-certificates=$MOZILLA_CA_CERT_STORE_PACKAGE_VERSION \
         postfix=$POSTFIX_PACKAGE_VERSION \

ca-certificates-package-log.url

@@ -0,0 +1 @@
+https://git.alpinelinux.org/aports/log/main/ca-certificates?h=3.15-stable

postfix-package-log.url

@@ -1 +1 @@
-https://git.alpinelinux.org/aports/log/main/postfix
+https://git.alpinelinux.org/aports/log/main/postfix?h=3.15-stable