caddy: update to 2.7.6

In this version we've made several fixes and enhancements with help from
several contributors. Most changes are small, but some notable ones:

- The templates middleware is now officially extensible (experimentally). This
  means modules can add custom functions/actions for templates to execute.
- TLS storage cleaning is now synchronized across the cluster and remembered
  across restarts. This should greatly lower costs for expensive storage
  backends like DynamoDB.
- Placeholders are now evaluated in config for certificate loaders.
- Numerous bug fixes.

www/caddy/Makefile

@@ -1,7 +1,6 @@
-# $NetBSD: Makefile,v 1.80 2024/02/07 14:51:02 bsiegert Exp $
+# $NetBSD: Makefile,v 1.81 2024/03/16 17:09:44 bsiegert Exp $
 
-DISTNAME=	caddy-2.7.5
-PKGREVISION=	5
+DISTNAME=	caddy-2.7.6
 CATEGORIES=	www
 GITHUB_TAG=	v${PKGVERSION_NOREV}
 MASTER_SITES=	${MASTER_SITE_GITHUB:=caddyserver/}