Remove Geo-specific git version check

ee/lib/system_check/geo/git_version_check.rb

-module SystemCheck
-  module Geo
-    class GitVersionCheck < ::SystemCheck::App::GitVersionCheck
-      set_name -> { "Git version >= #{self.required_version} ?" }
-      set_check_pass -> { "yes (#{self.current_version})" }
-
-      def self.required_version
-        @required_version ||= Gitlab::VersionInfo.new(2, 9, 5)
-      end
-    end
-  end
-end

lib/tasks/gitlab/check.rake

@@ -451,7 +451,6 @@ namespace :gitlab do
       checks = [
         SystemCheck::Geo::LicenseCheck,
         SystemCheck::Geo::EnabledCheck,
-        SystemCheck::Geo::GitVersionCheck,
         SystemCheck::Geo::GeoDatabaseConfiguredCheck,
         SystemCheck::Geo::DatabaseReplicationCheck,
         SystemCheck::Geo::HttpConnectionCheck,

spec/ee/spec/lib/system_check/geo/git_version_check_spec.rb

-require 'spec_helper'
-
-describe SystemCheck::Geo::GitVersionCheck do
-  describe '#check?' do
-    subject { described_class.new.check? }
-
-    where(:git_version, :result) do
-      [
-        ['2.8.99', false],
-        ['2.9.0',  false],
-        ['2.9.4',  false],
-        ['2.9.5',  true],
-        ['2.9.55', true],
-        ['10.0.0', true]
-      ]
-    end
-
-    with_them do
-      before do
-        stub_git_version(git_version)
-      end
-
-      it { is_expected.to eq(result) }
-    end
-  end
-
-  def stub_git_version(version)
-    allow(described_class).to receive(:current_version) { Gitlab::VersionInfo.parse(version) }
-  end
-end