Bump version to v0.5.0

[ima1zumi]

Diff: v0.4.3...4928e06

[ima1zumi]

irb head has failed

Failure: test_autocomplete_with_showdoc_in_gaps_on_narrow_screen_left(IRB::RenderingTest::TestVTerm)
/home/runner/.rubies/ruby-head/lib/ruby/gems/3.4.0+0/bundler/gems/yamatanooroti-ec2ccedaf90e/lib/yamatanooroti/vterm.rb:114:in 'Yamatanooroti::VTermTestCaseModule#assert_screen'
/home/runner/work/reline/reline/irb/test/irb/yamatanooroti/test_rendering.rb:319:in 'IRB::RenderingTest::TestVTerm#test_autocomplete_with_showdoc_in_gaps_on_narrow_screen_left'
<"start IRB\n" + "001> IRB\n" + "PressIRB\n" + "IRB\n"> expected but was
<"start IRB\n" + "001> IR\n" + "     IRB\n">
diff:
  start IRB
? 001> IRB
- PressIRB
? IRB

Failure: test_autocomplete_with_showdoc_in_gaps_on_narrow_screen_right(IRB::RenderingTest::TestVTerm)
/home/runner/.rubies/ruby-head/lib/ruby/gems/3.4.0+0/bundler/gems/yamatanooroti-ec2ccedaf90e/lib/yamatanooroti/vterm.rb:114:in 'Yamatanooroti::VTermTestCaseModule#assert_screen'
/home/runner/work/reline/reline/irb/test/irb/yamatanooroti/test_rendering.rb:293:in 'IRB::RenderingTest::TestVTerm#test_autocomplete_with_showdoc_in_gaps_on_narrow_screen_right'
<"start IRB\n" + "001> IRB\n" + "     IRBPress Alt+\n" + "        IRB\n"> expected but was
<"start IRB\n" + "001> IR\n" + "     IRB\n">
diff:
  start IRB
? 001> IRB
-      IRBPress Alt+
?      IRB

[tompng]

I think ruby/irb#911 will fix test failure
I think master branch passes the test because master with irb is not using latest reline (the job log includes Installing reline 0.4.3) probably because version string includes suffix .pre.1