Disable strategy #2 (guessed MIME-type) and strategy #3 (filename
extension) and verify that a caller that asserts the correct MIME-type
as the `content_type` argument gets the right `FileType` member.

Add a parameterized test for strategy #2 (guessed MIME-type) that
disables strategies #1 and #3 so we know what's actually being tested.
Remove individual tests made redundant by the single parameterized test.

And remove legacy tests replaced by these.

Disable strategy #2 (guessed MIME-type) and strategy #3 (filename
extension) and verify that a caller that asserts the correct MIME-type
as the `content_type` argument gets the right `FileType` member.

Add a parameterized test for strategy #2 (guessed MIME-type) that
disables strategies #1 and #3 so we know what's actually being tested.
Remove individual tests made redundant by the single parameterized test.

And remove legacy tests replaced by these.

Disable strategy #2 (guessed MIME-type) and strategy #3 (filename
extension) and verify that a caller that asserts the correct MIME-type
as the `content_type` argument gets the right `FileType` member.

Add a parameterized test for strategy #2 (guessed MIME-type) that
disables strategies #1 and #3 so we know what's actually being tested.
Remove individual tests made redundant by the single parameterized test.

And remove legacy tests replaced by these.

Disable strategy #2 (guessed MIME-type) and strategy #3 (filename
extension) and verify that a caller that asserts the correct MIME-type
as the `content_type` argument gets the right `FileType` member.

Add a parameterized test for strategy #2 (guessed MIME-type) that
disables strategies #1 and #3 so we know what's actually being tested.
Remove individual tests made redundant by the single parameterized test.

And remove legacy tests replaced by these.