Apply coercion to allow round-trip of boolean through JSON

The field is_pause_custodial_account is declared as a Bool, but this
type restricst values to empty string, zero or one.  When served as
a JSON document, this gets converted to a JSON boolean 'true' or
'false'.  When parsed back to Perl, this becomes a JSON::Boolean
object.  JSON::Boolean objects do not match the type constraint of
Bool, and cannot be used to construct ..Document::Author.
In particular, this is breaking the ability to update the profiles
of metacpan in metacpan/metacpan-web/issues/2694

Adding `coerce => 1` allows the JSON::Boolean to get transformed to
'' or 1, permitting a round trip without changing any representation
of the boolean.

Author: nrdvana

lib/MetaCPAN/Document/Author.pm

@@ -106,6 +106,7 @@ has updated => (
 has is_pause_custodial_account => (
     is      => 'ro',
     isa     => Bool,
+    coerce  => 1,
     default => 0,
 );