bundle install failed on Mac OS X 11.3 about travis.rb

[dove-young]

Then when I tried sudo gem install json -v '2.5.1' --source 'https://rubygems.org/' it failed at the same error

sudo gem install json -v '2.5.1' --source 'https://rubygems.org/'                                                                           1
Building native extensions. This could take a while...
ERROR:  Error installing json:
	ERROR: Failed to build gem native extension.

    current directory: /Library/Ruby/Gems/2.6.0/gems/json-2.5.1/ext/json/ext/generator
/System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/bin/ruby -I /System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0 -r ./siteconf20210603-10858-uisfq1.rb extconf.rb
creating Makefile

current directory: /Library/Ruby/Gems/2.6.0/gems/json-2.5.1/ext/json/ext/generator
make "DESTDIR=" clean

current directory: /Library/Ruby/Gems/2.6.0/gems/json-2.5.1/ext/json/ext/generator
make "DESTDIR="
compiling generator.c
In file included from generator.c:1:
In file included from ./../fbuffer/fbuffer.h:5:
In file included from /Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/include/ruby-2.6.0/ruby.h:33:
/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/include/ruby-2.6.0/ruby/ruby.h:24:10: fatal error: 'ruby/config.h' file not found
#include "ruby/config.h"
         ^~~~~~~~~~~~~~~
/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/include/ruby-2.6.0/ruby/ruby.h:24:10: note: did not find header 'config.h' in framework 'ruby' (loaded from '/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/System/Library/Frameworks')
1 error generated.
make: *** [generator.o] Error 1

make failed, exit code 2

Gem files will remain installed in /Library/Ruby/Gems/2.6.0/gems/json-2.5.1 for inspection.
Results logged to /Library/Ruby/Gems/2.6.0/extensions/universal-darwin-20/2.6.0/json-2.5.1/gem_make.out

[DerikLu]

same error on MacOS 11.7, any suggestion ?