[Integrated] RFR: Make Host::user return Optional<String>

[Erik Helin]

Changeset: 57f1d634
Author:    Erik Helin <ehelin at openjdk.org>
Date:      2020-02-14 10:52:05 +0000
URL:       https://git.openjdk.java.net/skara/commit/57f1d634

Make Host::user return Optional<String>

Reviewed-by: rwestberg

! bots/notify/src/main/java/org/openjdk/skara/bots/notify/IssueUpdater.java
! bots/tester/src/test/java/org/openjdk/skara/bots/tester/InMemoryContinuousIntegration.java
! bots/tester/src/test/java/org/openjdk/skara/bots/tester/InMemoryHost.java
! cli/src/main/java/org/openjdk/skara/cli/GitPr.java
! forge/src/main/java/org/openjdk/skara/forge/github/GitHubHost.java
! forge/src/main/java/org/openjdk/skara/forge/gitlab/GitLabHost.java
! forge/src/main/java/org/openjdk/skara/forge/gitlab/GitLabMergeRequest.java
! host/src/main/java/org/openjdk/skara/host/Host.java
! issuetracker/src/main/java/org/openjdk/skara/issuetracker/jira/JiraHost.java
! issuetracker/src/test/java/org/openjdk/skara/issuetracker/IssueTrackerTests.java
! test/src/main/java/org/openjdk/skara/test/TestHost.java