Stop crashing on failed Agda invocation

Signed-off-by: Danila Fedorin <danila.fedorin@gmail.com>

build-agda-html.rb

@@ -32,6 +32,8 @@ files_for_paths.each do |path, files|
   files.each do |file|
     puts "Invoking 'agda' on file: #{File.join [Dir.getwd, file]}"
     `#{ARGV[0]} --local-interfaces #{file} --html --html-dir=html`
-    fail unless $? == 0
+
+    # Allow some programs to fail (e.g., IO.agda in SPA without --guardedness)
+    # fail unless $? == 0
   end
 end