actionview: Make a block to url helpers optional

These helper methods can be called without block.  So it would be better
to declare as optional.

gems/actionview/6.0/actionview.rbs

@@ -163,7 +163,7 @@ module ActionView
       #
       #   link_to "External link", "http://www.rubyonrails.org/", target: "_blank", rel: "nofollow"
       #   # => <a href="http://www.rubyonrails.org/" target="_blank" rel="nofollow">External link</a>
-      def link_to: (?untyped? name, ?untyped? options, ?untyped? html_options) { () -> untyped } -> untyped
+      def link_to: (?untyped? name, ?untyped? options, ?untyped? html_options) ?{ () -> untyped } -> untyped
 
       # Generates a form containing a single button that submits to the URL created
       # by the set of +options+. This is the safest method to ensure links that
@@ -257,7 +257,7 @@ module ActionView
       #   #       <input name="authenticity_token" type="hidden" value="10f2163b45388899ad4d5ae948988266befcb6c3d1b2451cf657a0c293d605a6"/>
       #   #     </form>"
       #   #
-      def button_to: (?untyped? name, ?untyped? options, ?untyped? html_options) { () -> untyped } -> untyped
+      def button_to: (?untyped? name, ?untyped? options, ?untyped? html_options) ?{ () -> untyped } -> untyped
 
       # Creates a link tag of the given +name+ using a URL created by the set of
       # +options+ unless the current request URI is the same as the links, in
@@ -297,7 +297,7 @@ module ActionView
       #           link_to("Go back", { controller: "posts", action: "index" })
       #        end
       #     %>
-      def link_to_unless_current: (untyped name, ?::Hash[untyped, untyped] options, ?::Hash[untyped, untyped] html_options) { () -> untyped } -> untyped
+      def link_to_unless_current: (untyped name, ?::Hash[untyped, untyped] options, ?::Hash[untyped, untyped] html_options) ?{ () -> untyped } -> untyped
 
       # Creates a link tag of the given +name+ using a URL created by the set of
       # +options+ unless +condition+ is true, in which case only the name is
@@ -319,7 +319,7 @@ module ActionView
       #   # => <a href="/controller/reply/">Reply</a>
       #   # If not...
       #   # => <a href="/accounts/signup">Reply</a>
-      def link_to_unless: (untyped condition, untyped name, ?::Hash[untyped, untyped] options, ?::Hash[untyped, untyped] html_options) { () -> untyped } -> untyped
+      def link_to_unless: (untyped condition, untyped name, ?::Hash[untyped, untyped] options, ?::Hash[untyped, untyped] html_options) ?{ () -> untyped } -> untyped
 
       # Creates a link tag of the given +name+ using a URL created by the set of
       # +options+ if +condition+ is true, otherwise only the name is
@@ -341,7 +341,7 @@ module ActionView
       #   # => <a href="/sessions/new/">Login</a>
       #   # If they are logged in...
       #   # => <a href="/accounts/show/3">my_username</a>
-      def link_to_if: (untyped condition, untyped name, ?::Hash[untyped, untyped] options, ?::Hash[untyped, untyped] html_options) { () -> untyped } -> untyped
+      def link_to_if: (untyped condition, untyped name, ?::Hash[untyped, untyped] options, ?::Hash[untyped, untyped] html_options) ?{ () -> untyped } -> untyped
 
       # Creates a mailto link tag to the specified +email_address+, which is
       # also used as the name of the link unless +name+ is specified. Additional
@@ -381,7 +381,7 @@ module ActionView
       #   # => <a href="mailto:[email protected]">
       #          <strong>Email me:</strong> <span>[email protected]</span>
       #        </a>
-      def mail_to: (untyped email_address, ?untyped? name, ?::Hash[untyped, untyped] html_options) { () -> untyped } -> untyped
+      def mail_to: (untyped email_address, ?untyped? name, ?::Hash[untyped, untyped] html_options) ?{ () -> untyped } -> untyped
 
       # True if the current request URI was generated by the given +options+.
       #