Stack trace of exceptions are not being logged

[rksk]

Description:
There are multiple places where we do not print the stack trace of exceptions in error logs. Because the following format is used to log errors. For example [1], [2]
log.error("msg" + e)

It will be very helpful to debug issues if we use the following way to log exceptions.
log.error("msg", e)

[1] https://github.com/wso2/carbon-identity-framework/blob/master/components/entitlement/org.wso2.carbon.identity.entitlement/src/main/java/org/wso2/carbon/identity/entitlement/pip/CarbonAttributeFinder.java#L209
[2] https://github.com/wso2/carbon-identity-framework/blob/master/components/carbon-authenticators/thrift-authenticator/org.wso2.carbon.identity.authenticator.thrift/src/main/java/org/wso2/carbon/identity/thrift/authentication/internal/ThriftAuthenticationServiceComponent.java#L187