Allow the JKSLoader to continue in case jks.properties file does not exist.

[chamathns]

Describe the issue:
Currently, the app deployment fails if the jks.properties file is not available in the resources.

How to reproduce:
Integrate the tomcat-oidc-agent to an existing application. [1]
Don't include the jks.properties file in the app WEB-INF/classes directory.
Deploy the app.
App deployment fails.

Expected behavior:
App should deploy without any errors.

[1] https://github.com/asgardeo/asgardeo-tomcat-oidc-agent#to-your-existing-webapp