Add missing invocant markers in Date.methods

Author: lizmat

doc/Type/Date.pod6

@@ -181,8 +181,8 @@ Returns the invocant.
 
 =head2 method DateTime
 
-    multi method DateTime(Date:U --> DateTime:U)
-    multi method DateTime(Date:D --> DateTime:D)
+    multi method DateTime(Date:U: --> DateTime:U)
+    multi method DateTime(Date:D: --> DateTime:D)
 
 Converts the invocant to L«C<DateTime>|/type/DateTime»
 
@@ -191,7 +191,7 @@ Converts the invocant to L«C<DateTime>|/type/DateTime»
 
 =head2 method Int
 
-    multi method Int(Date:D --> Int:D)
+    multi method Int(Date:D: --> Int:D)
 
 Converts the invocant to L«C<Int>|/type/Int».  The same value can be
 obtained with the C<daycount> method.
@@ -200,7 +200,7 @@ Available as of release 2023.02 of the Rakudo compiler.
 
 =head2 method Real
 
-    multi method Real(Date:D --> Int:D)
+    multi method Real(Date:D: --> Int:D)
 
 Converts the invocant to L«C<Int>|/type/Int».  The same value can be
 obtained with the C<daycount> method.
@@ -209,7 +209,7 @@ Available as of release 2023.02 of the Rakudo compiler.
 
 =head2 method Numeric
 
-    multi method Numeric(Date:D --> Int:D)
+    multi method Numeric(Date:D: --> Int:D)
 
 Converts the invocant to L«C<Int>|/type/Int».  The same value can be
 obtained with the C<daycount> method.  This allows C<Date> objects to