Ensure all docker files are updated.

[lutkerd]

Ran locally without and without the additional sed commands from previous commit and it is worked as expected.

+ MAJOR_RELEASE=8
+ VERSION_STRING=383
+ pushd 8
~/code/corretto-docker/8 ~/code/corretto-docker
++ find ./ -name Dockerfile
++ wc -l
+ DOCKERFILE_COUNT=14
++ grep -rl 383 --include Dockerfile
++ wc -l
+ UPDATED_DOCKERFILE_COUNT=12
+ echo 'Updated 12 files for Corretto-8'
Updated 12 files for Corretto-8
+ [[ 14 == 12 ]]
+ echo 'Error: 14 updated were expected!'
Error: 14 updated were expected!