Recursively add file extension to all files

laptop:/srv# touch script{0..9}
laptop:/srv# ls
script0 script1 script2 script3 script4 script5 script6 script7 script8 script9
laptop:/srv# find . -type f -exec mv '{}' '{}'.sh \; ; ls
script0.sh script2.sh script4.sh script6.sh script8.sh
script1.sh script3.sh script5.sh script7.sh script9.sh
laptop:/srv# rm -f script* && touch script{0..9}
laptop:/srv# find . -type f -not -name "." -print0 | xargs -0 rename 's/(.)$/$1.sh/'; ls
script0.sh script2.sh script4.sh script6.sh script8.sh
script1.sh script3.sh script5.sh script7.sh script9.sh