PS-9500: AppArmor denies access to files /proc/self/task/<tid>/mem

Access to /proc/$pid/task/$thread_id/mem is required by stacktrace code.

We apply the same changes as upstream did at
mysql/mysql-server@b76c48b031d

Author: inikep

build-ps/debian/extra/apparmor-profile

@@ -12,6 +12,7 @@
   /sys/devices/system/node/ r,
   /sys/devices/system/node/** r,
   /proc/*/status r,
+  /proc/*/mem r,
   capability sys_resource,
   capability dac_override,
   capability setuid,

build-ps/debian/extra/apparmor.d/old_apparmor

@@ -12,6 +12,7 @@
   /sys/devices/system/node/ r,
   /sys/devices/system/node/** r,
   /proc/*/status r,
+  /proc/*/mem r,
   capability sys_resource,
   capability dac_override,
   capability setuid,

build-ps/debian/extra/apparmor.d/usr.sbin.mysqld.in2

@@ -12,6 +12,7 @@
   /sys/devices/system/node/ r,
   /sys/devices/system/node/** r,
   /proc/*/status r,
+  /proc/*/mem r,
   capability sys_resource,
   capability dac_override,
   capability setuid,