Add workaround for CI failure

[ima1zumi]

The system on CI rake version is 13.0.6, while the bundle installing rake version is 13.1.0.
IRB's test on CI depends on the system's rake document.
Match the rake version installed on system to the version installed by bundler.

[st0012]

Thank you for the fix but I don't fully understand the root cause and how this resolved it. Is it because 13.1.0 is installed without document so IRB couldn't find the doc? Do we rely on rake's document, or we rely on it to generate document?

[tompng]

The failing test test_autocomplete_with_showdoc_in_gaps_on_narrow_screen_right and test_autocomplete_with_showdoc_in_gaps_on_narrow_screen_left is showing document of String.
It is depending on rake because rake includes document of string and system doc is not available on ci.

$ mv /opt/ruby/share/ri/3.3.0+0/system /opt/ruby/share/ri/3.3.0+0/system_
$ ri String
= String < Object

(from gem rake-13.1.0)
------------------------------------------------------------------------
= Instance methods:

  ext, pathmap, pathmap_explode, pathmap_partial, pathmap_replace

[st0012]

Wow that's pretty wild. Can we maybe use StandardError in the test case to make sure we always look for the doc from Ruby Core?

[tompng]

Ruby core's document including StandardError is not available on ci. (I don't. know why)

I don't think we should rely on it. If we rely on it, maybe we should explicitly show Rake's document in test.

write("require 'rake')
write("Rake\C-i")

There are some workaround variation. I merged this because I think it's worth first add this workaround to make ci green.

[st0012]

I merged this because I think it's worth first add this workaround to make ci green.

Oh I totally agree with this 👍
I'm asking to make sure we know what to do next so we don't get bitten by the same problem again later.

I think we may just use IRB's own content for this. I will open a PR later.