The SSL connection to the database is failing, try changing your datasource URL to:
so Either you change the URL in config file like for example
in Tomcat in server.xml add "useSSL=false" in the end of the complete url as below

spring.datasource.url=jdbc:mysql://localhost:3306/employee_database?useSSL=false

=================OR===================
ADD the below line to your mysql database config file

ssl=0