feat: Generate and add ex-request-id response header

[zvigrinberg]

1. Generate ex-request-id , a sha256 digest of the timestamp + rhda_token if exists ( otherwise random real number in the range of [0,1] ).

2. add this generated value as an exchange property ( Camel exchange property) called exRequestId.

3. propagate it to all original request message paths , all error messages and on all error paths as a metadata field with the name of the property.

4. add to the response of all paths and cases( 200, 422 , 5xx , etc.) the value of generted ex-request-id as a response header.

Handle: https://issues.redhat.com/browse/APPENG-2183.

Why not using UUID generator and that's it?
Because RHDA Token is already one of the metadata fields in logs messages sent to sentry, and usually clients send RHDA Token as Pseudo random generated uuid, and we want a different pattern of randomly generated unique string not to be confused with RHDA Token:

1. The size is much bigger - 64 characters, hence it can be instantly looked up in the logs and found, without any fear for collision ( chances for collisions are very near to zero, much more close to zero than just standard UUID because of the string size).
2. It can't be confused with RHDA-TOKEN' UUID value as uuid' length is much shorter and also with hyphens, and sha256 string digest is a string of 64 charcters long of hexadecimal characters.

[ruromero]

@zvigrinberg the solution looks consistent. I have just added some small remarks and comments

[ruromero]

LGTM thanks for the changes