fix: simplify the logic about base classes in record.hbs

Author: gennaroprota

share/mrdocs/addons/generator/common/partials/symbol/signature/record.hbs

@@ -7,8 +7,7 @@
     {{>symbol/name-text symbol ~}}
 {{~/if}}
 {{~#if isFinal}} final{{/if~}}
-{{#unless bases~}}
-{{else}}
+{{#if bases}}
 
 {{#each bases~}}
     {{#if @first}}
@@ -17,7 +16,7 @@
     {{#unless (eq access ../defaultAccess)}} {{access}}{{/unless~}}
     {{#if isVirtual}} virtual{{/if}} {{>type/declarator type~}}
 {{/each~}}
-{{/unless}}
+{{/if}}
 {{!-- Unless we are going to show a class body ("{ ... }"), don't add a
       semicolon if the record is final, because something like `class A
       final;` is ill-formed (`final` can't be used on a non-defining