SONAR-17271 Introduce Github code scanning alert webhook payload parser

SONAR-17271 Introduce Github code scanning alert webhook payload parser

* 292a9c66137 SONAR-17271 Rename `GsonGithubWebhookPayload` class to `GsonGithubCodeScanningAlertWebhookPayload`.
* 0fcf756bc35 SONAR-17271 Rename `GithubWebhookPayload` indentifiers to `GithubScanningAlertWebhookPayload`.
* 9882b4f6705 SONAR-17271 Remove `GithubWebhookPayload#message` & `GithubWebhookPayload#toolName` properties.
* ba6834fef16 SONAR-17271 Validate builder parameters in `GithubWebhookPayload` constructor scope.
* 7250cb15b92 SONAR-17271 Allow `dismissedReason` property to be nullable.
* 870efb823e3 SONAR-17271 Introduce builder pattern to `GithubWebhookPayload` class.
* aa49dead5f0 SONAR-17271 Remove `GithubWebhookAction` enum.
* dda46050d40 SONAR-17271 Refactor `GithubWebhookPayloadTest` test class.
* 3a599896295 SONAR-17271 Rename `AlmWebhookPayload#getSonarIssueKey` supplier method to `AlmWebhookPayload#getSonarQubeIssueKey`.
* de04692e92d SONAR-17271 Drop `AlmWebhookPayload#isAllowedAction` predicate method.
* 597570d36b0 SONAR-17271 Refactor `GithubBinding` class structure.
* 3054bcedbac SONAR-17271 Fix typo on UT identifier.
* c89660c466b SONAR-17271 Introduce Github webhook payload parser.