[land-bot] Improve error reporting when fetching revision status fails
Summary:
Prior to this patch, the request can fail for a number of reasons and provide
no helpful info to investigate the issue.
Test Plan:
vim land-patch.sh # edit the domain on the REVISION_STATUS line to a non-existent domain CONDUIT_TOKEN=invalid ./land-patch --dry-run -r D5930 # Failed to connect to non-existent domain git reset --hard <this-patch> CONDUIT_TOKEN=invalid ./land-patch --dry-run -r D5930 # Gives Conduit error as expected CONDUIT_TOKEN=<valid-token> ./land-patch --dry-run -r D5930 # Still errors as expected since this revision isn't accepted
Reviewers: #bitcoin_abc, Fabien
Reviewed By: #bitcoin_abc, Fabien
Differential Revision: https://reviews.bitcoinabc.org/D6143