ARROW-7515: [C++] Rename nonexistent and non_existent to not_found

[mrkn]

No description provided.

[github-actions]

https://issues.apache.org/jira/browse/ARROW-7515

[mrkn]

@nealrichardson Could you tell me the way to fix the following warning?

https://github.com/apache/arrow/pull/6139/checks?check_run_id=395390711#step:5:988

* checking for code/documentation mismatches ... WARNING
Codoc mismatches from documentation object 'open_source':
open_source
  Code: function(path, filesystem = c("auto", "local"), format =
                 c("parquet", "arrow", "ipc"), partitioning = NULL,
                 allow_not_found = FALSE, recursive = TRUE, ...)
  Docs: function(path, filesystem = c("auto", "local"), format =
                 c("parquet", "arrow", "ipc"), partitioning = NULL,
                 allow_non_existent = FALSE, recursive = TRUE, ...)
  Argument names in code not in docs:
    allow_not_found
  Argument names in docs not in code:
    allow_non_existent
  Mismatches in argument names:
    Position: 5 Code: allow_not_found Docs: allow_non_existent

[nealrichardson]

@mrkn edit r/man/open_source.Rd to match the inline doc source you edited. Better would be to run make doc from the r/ directory to regenerate the docs, though that requires that you have R set up and dependencies installed.

[wesm]

This needs to be rebased. @pitrou what do you think about this? I think it's okay

[mrkn]

@kou I added a commit for renaming things in c_glib.

[pitrou]

@mrkn Looks like the Ruby tests fails on Github Actions. You may be able to reproduce locally using:

docker-compose run ubuntu-ruby

[kou]

+1

I've pushed some more nonexistent to not-found changes.
And I've fixed GLib test failures.

[mrkn]

@kou thank you!

[kou]

I found more "nonexistent".
I've renamed them to "not found".
Python jobs will be green.

[mrkn]

@kou Thank you, again!

@pitrou Could you review this again?