Don't build extension libs for bundled gems

ruby/ruby@2c4170e

Author: kateinoigakukun

lib/ruby_wasm/packager.rb

@@ -67,7 +67,7 @@ def support_dynamic_linking?
   end
 
   ALL_DEFAULT_EXTS =
-    "bigdecimal,cgi/escape,continuation,coverage,date,dbm,digest/bubblebabble,digest,digest/md5,digest/rmd160,digest/sha1,digest/sha2,etc,fcntl,fiber,gdbm,json,json/generator,json/parser,nkf,objspace,pathname,psych,racc/cparse,rbconfig/sizeof,ripper,stringio,strscan,monitor,zlib,openssl"
+    "cgi/escape,continuation,coverage,date,digest/bubblebabble,digest,digest/md5,digest/rmd160,digest/sha1,digest/sha2,etc,fcntl,json,json/generator,json/parser,objspace,pathname,psych,rbconfig/sizeof,ripper,stringio,strscan,monitor,zlib,openssl"
 
   # Retrieves the build options used for building Ruby itself.
   def build_options