Set default osx_image value to xcode10.1 on macOS

EwoutH February 6, 2019, 11:25am 1

xcode10.1 / xcode10.x is, in my opinion, stable enough to be set as the default image on macOS.

Topic		Replies	Views
The default `osx_image: xcode9.4` is now unusable because MacOS 10.13 is EOL macOS bug , homebrew	2	962	February 5, 2021
Please add image for Xcode 10.2 beta macOS build-env	1	1003	March 7, 2019
Xcode beta 6 image update macOS	1	642	August 30, 2019
Xcode11.6 MacOS image still uses Xcode 11.6 beta macOS	4	689	July 29, 2020
Document osx_image: xcode11.4 macOS	0	744	April 14, 2020