stubby: reduce idle_timeout as recommended upstream

Reduce idle_timeout parameter from 10s to 9s as recommended upstream
Add a pointer to upstream documentation

Ref: 7f07bde70e/stubby.yml.example (L249)
Signed-off-by: Andris PE <neandris@gmail.com>

net/stubby/Makefile

@@ -6,7 +6,7 @@ include $(TOPDIR)/rules.mk
 
 PKG_NAME:=stubby
 PKG_VERSION:=0.4.3
-PKG_RELEASE:=2
+PKG_RELEASE:=3
 
 PKG_SOURCE_PROTO:=git
 PKG_SOURCE_URL:=https://github.com/getdnsapi/$(PKG_NAME)

net/stubby/files/stubby.conf

@@ -13,7 +13,7 @@ config stubby 'global'
        # option trust_anchors_backoff_time 2500
        # option dnssec_trust_anchors '/var/lib/stubby/getdns-root.key'
        option edns_client_subnet_private '1'
-       option idle_timeout '10000'
+       option idle_timeout '9000'
        option round_robin_upstreams '1'
        list listen_address '127.0.0.1@5453'
        list listen_address '0::1@5453'
@@ -25,6 +25,8 @@ config stubby 'global'
        # option tls_max_version '1.3'
 
 # Upstream resolvers are specified using 'resolver' sections.
+# Extensive list of public DoT servers can be found in upstream stubby sources
+#  https://github.com/getdnsapi/stubby/blob/develop/stubby.yml.example
 config resolver
        option address '2606:4700:4700::1111'
        option tls_auth_name 'cloudflare-dns.com'

net/stubby/files/stubby.yml

@@ -8,7 +8,7 @@ appdata_dir: "/var/lib/stubby"
 tls_authentication: GETDNS_AUTHENTICATION_REQUIRED
 tls_query_padding_blocksize: 128
 edns_client_subnet_private: 1
-idle_timeout: 10000
+idle_timeout: 9000
 listen_addresses:
   - 127.0.0.1@5453
   - 0::1@5453