Revert "Return tag along with commit"

This reverts commit c2fc97b138.

The respective change in travis-core was reverted meanwhile:
95d59342e9

lib/travis/api/v2/http/build.rb

@@ -48,7 +48,6 @@ module Travis
                 'id' => commit.id,
                 'sha' => commit.commit,
                 'branch' => commit.branch,
-                'tag'    => commit.tag,
                 'message' => commit.message,
                 'committed_at' => format_date(commit.committed_at),
                 'author_name' => commit.author_name,

lib/travis/api/v2/http/builds.rb

@@ -49,7 +49,6 @@ module Travis
                 'id' => commit.id,
                 'sha' => commit.commit,
                 'branch' => commit.branch,
-                'tag' => commit.tag,
                 'message' => commit.message,
                 'committed_at' => format_date(commit.committed_at),
                 'author_name' => commit.author_name,

lib/travis/api/v2/http/job.rb

@@ -47,7 +47,6 @@ module Travis
                 'id' => commit.id,
                 'sha' => commit.commit,
                 'branch' => commit.branch,
-                'tag' => commit.tag,
                 'message' => commit.message,
                 'committed_at' => format_date(commit.committed_at),
                 'author_name' => commit.author_name,

lib/travis/api/v2/http/jobs.rb

@@ -45,7 +45,6 @@ module Travis
                 'id' => commit.id,
                 'sha' => commit.commit,
                 'branch' => commit.branch,
-                'tag' => commit.tag,
                 'message' => commit.message,
                 'committed_at' => format_date(commit.committed_at),
                 'author_name' => commit.author_name,

spec/unit/api/v2/http/build_spec.rb

@@ -28,7 +28,6 @@ describe Travis::Api::V2::Http::Build do
       'id' => 1,
       'sha' => '62aae5f70ceee39123ef',
       'branch' => 'master',
-      'tag' => nil,
       'message' => 'the commit message',
       'compare_url' => 'https://github.com/svenfuchs/minimal/compare/master...develop',
       'committed_at' => json_format_time(Time.now.utc - 1.hour),

spec/unit/api/v2/http/builds_spec.rb

@@ -28,7 +28,6 @@ describe Travis::Api::V2::Http::Builds do
       'id' => commit.id,
       'sha' => '62aae5f70ceee39123ef',
       'branch' => 'master',
-      'tag' => nil,
       'message' => 'the commit message',
       'compare_url' => 'https://github.com/svenfuchs/minimal/compare/master...develop',
       'committed_at' => json_format_time(Time.now.utc - 1.hour),

spec/unit/api/v2/http/job_spec.rb

@@ -31,7 +31,6 @@ describe Travis::Api::V2::Http::Job do
       'sha' => '62aae5f70ceee39123ef',
       'message' => 'the commit message',
       'branch' => 'master',
-      'tag' => nil,
       'message' => 'the commit message',
       'committed_at' => json_format_time(Time.now.utc - 1.hour),
       'committer_name' => 'Sven Fuchs',

spec/unit/api/v2/http/jobs_spec.rb

@@ -30,7 +30,6 @@ describe Travis::Api::V2::Http::Jobs do
       'sha' => '62aae5f70ceee39123ef',
       'message' => 'the commit message',
       'branch' => 'master',
-      'tag' => nil,
       'message' => 'the commit message',
       'committed_at' => json_format_time(Time.now.utc - 1.hour),
       'committer_name' => 'Sven Fuchs',