swift

7f70d33e - [QoI] Say "'@objc'" rather than the redundant "'@objc' attribute" in diagnostics.

[QoI] Say "'@objc'" rather than the redundant "'@objc' attribute" in diagnostics. A cleanup Jordan had mentioned a while ago that I'd forgotten about, which makes the diagnostics slightly shorter. (cherry picked from commit 9f50a0ec61d09ec261f08b9a9c4bab5f4050eca7)