/var/lib/dpkg/info/mysql-server-5.7.postinst: line 143: /usr/share/mysql-common/configure-symlinks: No such file or directory

This is a common problem after MySQL upgrade.

The issue is, the symlink /usr/share/mysql-common/configure-symlinks doesn't exist.

Just create the symlink and run apt upgrade or apt-get upgrade and it will work

We can do the following to fix the issue

touch $$ : this creates a file with a unique name.

touch /tmp/$$.$$ ; cd /usr/share/mysql-common/ ; ln -s /tmp/$$.$$ /usr/share/mysql-common/configure-symlinks ; chmod 777 /usr/share/mysql-common/configure-symlinks ; apt -y upgrade ; rm -f /tmp/$$.$$