The HeadObject path translates a 404 (Not Found) and a 405 (Method Not
Allowed) response into fs.ErrorObjectNotFound, but the GetObject path
returns the raw AWS SDK error instead. With --s3-no-head-object set,
Object.Open() is the first request to hit the source for a GET
operation, so callers that rely on fs.ErrorObjectNotFound see an
opaque "operation error S3: GetObject, ... StatusCode: 404" string
when --s3-no-head-object is set.
Mirror the error handling of HeadObject. The 405 (Method Not Allowed)
case applies to GetObject for the same reason it applies to
HeadObject: A request that specifies the versionId of a delete marker
returns 405 instead of 404 (commit 8470bdf810, AWS S3 delete-marker
docs).
Co-authored-by: Jan Schlien <rclone-github@jan-o-sch.net>
c1df24f142