MINOR: specification: allow HAProxy variables in object name fields

Relax name regex on peer entries, nameservers, mailer entries, userlist
groups/users, and frontend log_tag to accept ${VAR} substitution. Section
names are unchanged.

Author: mjuraga

models/frontend_base.go

@@ -3056,7 +3056,7 @@ definitions:
           - disabled
         type: string
       log_tag:
-        pattern: ^[A-Za-z0-9-_.:]+$
+        pattern: ^[A-Za-z0-9-_.:${}]+$
         type: string
       logasap:
         enum:
@@ -3942,7 +3942,7 @@ definitions:
       secure_password:
         type: boolean
       username:
-        pattern: ^[A-Za-z0-9-_.:]+$
+        pattern: ^[A-Za-z0-9-_.:${}]+$
         type: string
         x-nullable: false
     required:
@@ -3961,7 +3961,7 @@ definitions:
     description: HAProxy userlist group
     properties:
       name:
-        pattern: ^[A-Za-z0-9-_.:]+$
+        pattern: ^[A-Za-z0-9-_.:${}]+$
         type: string
         x-nullable: false
       users:
@@ -4021,7 +4021,7 @@ definitions:
         type: string
         x-nullable: false
       name:
-        pattern: ^[A-Za-z0-9-_]+$
+        pattern: ^[A-Za-z0-9-_${}]+$
         type: string
         x-nullable: false
       port:
@@ -4104,7 +4104,7 @@ definitions:
         pattern: ^[^\s]+$
         type: string
       name:
-        pattern: ^[A-Za-z0-9-_.:]+$
+        pattern: ^[A-Za-z0-9-_.:${}]+$
         type: string
         x-nullable: false
       port:
@@ -10015,7 +10015,7 @@ definitions:
         pattern: ^[^\s]+$
         type: string
       name:
-        pattern: ^[A-Za-z0-9-_.:]+$
+        pattern: ^[A-Za-z0-9-_.:${}]+$
         type: string
         x-nullable: false
       port:

models/group.go

@@ -86,7 +86,7 @@ frontend_base:
       x-display-name: Log Format SD
     log_tag:
       type: string
-      pattern: '^[A-Za-z0-9-_.:]+$'
+      pattern: '^[A-Za-z0-9-_.:${}]+$'
     log_separate_errors:
       type: string
       enum: [enabled, disabled]

models/mailer_entry.go

@@ -40,7 +40,7 @@ mailer_entry:
   properties:
     name:
       type: string
-      pattern: '^[A-Za-z0-9-_]+$'
+      pattern: '^[A-Za-z0-9-_${}]+$'
       x-nullable: false
     address:
       type: string

models/nameserver.go

@@ -60,7 +60,7 @@ peer_entry:
   properties:
     name:
       type: string
-      pattern: '^[A-Za-z0-9-_.:]+$'
+      pattern: '^[A-Za-z0-9-_.:${}]+$'
       x-nullable: false
     address:
       type: string