Add PHP 8.4 support

Dockerfile.template

@@ -88,7 +88,12 @@ RUN set -ex; \
 # WARNING: imagick is likely not supported on Alpine: https://github.com/Imagick/imagick/issues/328
 {{ ) else "" end -}}
 # https://pecl.php.net/package/imagick
-{{ if true then ( -}}
+{{ if env.phpVersion == "8.4" then ( -}}
+# RC for PHP 8.4 because of https://github.com/Imagick/imagick/issues/689
+	pecl install imagick-3.8.0RC2; \
+	docker-php-ext-enable imagick; \
+	rm -r /tmp/pear; \
+{{ ) else ( -}}
 # https://github.com/Imagick/imagick/commit/5ae2ecf20a1157073bad0170106ad0cf74e01cb6 (causes a lot of build failures, but strangely only intermittent ones 🤔)
 # see also https://github.com/Imagick/imagick/pull/641
 # this is "pecl install imagick-3.7.0", but by hand so we can apply a small hack / part of the above commit
@@ -101,11 +106,7 @@ RUN set -ex; \
 	grep '^//#endif$' /tmp/imagick-3.7.0/Imagick.stub.php && exit 1 || :; \
 	docker-php-ext-install /tmp/imagick-3.7.0; \
 	rm -rf imagick.tgz /tmp/imagick-3.7.0; \
-{{ # TODO when imagick has another release, we should ditch this whole block and just update instead -}}
-{{ ) else ( -}}
-	pecl install imagick-3.7.0; \
-	docker-php-ext-enable imagick; \
-	rm -r /tmp/pear; \
+{{ # TODO when 3.8.0 is GA, we should ditch this whole block and just update instead -}}
 {{ ) end -}}
 	\
 # some misbehaving extensions end up outputting to stdout 🙈 (https://github.com/docker-library/wordpress/issues/669#issuecomment-993945967)