Brief summary of the bug. What is it ? Where is it ?

When creating an OptimizeLicense.txt in the sso example config folder it's not read by the Optimize container.

Steps to reproduce:

1. Put a valid license into the template file https://github.com/camunda/camunda-optimize-examples/blob/master/optimize-sso-keycloak-example/optimize-config/OptimizeLicense.txt of the keycloak sso example.
2. start the sample
3. Login to Optimize

What is the actual result of running the mentioned steps. If it is possible please add screenshots, videos or log files and highlight the error or draw the area where the bug is.

4. You are asked to input a license

Expected result:

The license should be read from the file