Drop the HipChat plugin

https://en.wikipedia.org/wiki/HipChat says:
> Following this, HipChat and Stride customers were migrated to the
> Slack group collaboration platform in a transition that was completed by
> February 2019.

doc/manual/src/plugins/README.md

@@ -172,17 +172,6 @@ Sets Gitlab CI status.
 
 - `gitlab_authorization.<projectId>`
 
-## HipChat notification
-
-Sends hipchat chat notifications when a build finish.
-
-### Configuration options
-
-- `hipchat.[].jobs`
-- `hipchat.[].builds`
-- `hipchat.[].token`
-- `hipchat.[].notify`
-
 ## InfluxDB notification
 
 Writes InfluxDB events when a builds finished.

src/lib/Hydra/Plugin/HipChatNotification.pm

@@ -1,89 +0,0 @@
-package Hydra::Plugin::HipChatNotification;
-
-use strict;
-use warnings;
-use parent 'Hydra::Plugin';
-use LWP::UserAgent;
-use Hydra::Helper::CatalystUtils;
-
-sub isEnabled {
-    my ($self) = @_;
-    return defined $self->{config}->{hipchat};
-}
-
-sub buildFinished {
-    my ($self, $topbuild, $dependents) = @_;
-
-    my $cfg = $self->{config}->{hipchat};
-    my @config = defined $cfg ? ref $cfg eq "ARRAY" ? @$cfg : ($cfg) : ();
-
-    my $baseurl = $self->{config}->{'base_uri'} || "http://localhost:3000";
-
-    # Figure out to which rooms to send notification.  For each email
-    # room, we send one aggregate message.
-    my %rooms;
-    foreach my $build ($topbuild, @{$dependents}) {
-        my $prevBuild = getPreviousBuild($build);
-        my $jobName = showJobName $build;
-
-        foreach my $room (@config) {
-            my $force = $room->{force};
-            next unless $jobName =~ /^$room->{jobs}$/;
-
-            # If build is cancelled or aborted, do not send email.
-            next if ! $force && ($build->buildstatus == 4 || $build->buildstatus == 3);
-
-            # If there is a previous (that is not cancelled or aborted) build
-            # with same buildstatus, do not send email.
-            next if ! $force && defined $prevBuild && ($build->buildstatus == $prevBuild->buildstatus);
-
-            $rooms{$room->{room}} //= { room => $room, builds => [] };
-            push @{$rooms{$room->{room}}->{builds}}, $build;
-        }
-    }
-
-    return if scalar keys %rooms == 0;
-
-    my ($authors, $nrCommits) = getResponsibleAuthors($topbuild, $self->{plugins});
-
-    # Send a message to each room.
-    foreach my $roomId (keys %rooms) {
-        my $room = $rooms{$roomId};
-        my @deps = grep { $_->id != $topbuild->id } @{$room->{builds}};
-
-        my $img =
-            $topbuild->buildstatus == 0 ? "$baseurl/static/images/checkmark_16.png" :
-            $topbuild->buildstatus == 2 ? "$baseurl/static/images/dependency_16.png" :
-            $topbuild->buildstatus == 4 ? "$baseurl/static/images/cancelled_16.png" :
-            "$baseurl/static/images/error_16.png";
-
-        my $msg = "";
-        $msg .= "<img src='$img'/> ";
-        $msg .= "Job <a href='$baseurl/job/${\$topbuild->jobset->get_column('project')}/${\$topbuild->jobset->get_column('name')}/${\$topbuild->get_column('job')}'>${\showJobName($topbuild)}</a>";
-        $msg .= " (and ${\scalar @deps} others)" if scalar @deps > 0;
-        $msg .= ": <a href='$baseurl/build/${\$topbuild->id}'>" . showStatus($topbuild) . "</a>";
-
-        if (scalar keys %{$authors} > 0) {
-            # FIXME: HTML escaping
-            my @x = map { "<a href='mailto:$authors->{$_}'>$_</a>" } (sort keys %{$authors});
-            $msg .= ", likely due to ";
-            $msg .= "$nrCommits commits by " if $nrCommits > 1;
-            $msg .= join(" or ", scalar @x > 1 ? join(", ", @x[0..scalar @x - 2]) : (), $x[-1]);
-        }
-
-        print STDERR "sending hipchat notification to room $roomId: $msg\n";
-
-        my $ua = LWP::UserAgent->new();
-        my $resp = $ua->post('https://api.hipchat.com/v1/rooms/message?format=json&auth_token=' . $room->{room}->{token}, {
-            room_id => $roomId,
-            from => 'Hydra',
-            message => $msg,
-            message_format => 'html',
-            notify => $room->{room}->{notify} || 0,
-            color => $topbuild->buildstatus == 0 ? 'green' : 'red' });
-
-        print STDERR $resp->status_line, ": ", $resp->decoded_content,"\n" if !$resp->is_success;
-    }
-}
-
-1;