Log error message on editor error

[JamesLaverack]

What type of PR is this?

/kind cleanup

What this PR does / why we need it:

When running the krel release notes tool, there have been infrequent but repeated instances of exiting editors producing errors. See this thread from January 2022, and then a follow up report here in November 2023. This is a persistent, but highly intermittent issue. Users have also reported that it only seems to occur with vi.

The krel output logging in this instance says simply:

- Fix note for PR #97252? (y/N) (1/10) 
y
INFO Opening file with editor [vi /var/folders/94/yvfr6pns4vxd1bz_cr2nwpkc0000gn/T/release-notes-map-1064630614.yaml] 
FATA creating Draft PR: while running release notes fix flow: while editing release note: while launching editor: there was a problem with the editor "vi" 

This change modifies the error log to include the err that led to this case, so that future instances can lead to more productive debugging.

Which issue(s) this PR fixes:

None

Special notes for your reviewer:

None

Does this PR introduce a user-facing change?

Improve error logging during external editor failure

[saschagrunert]

Thanks!

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: JamesLaverack, saschagrunert

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