support for Catalina softwareupdate output

[w0de]

In Catalina, the output for software update appears so:

Software Update Tool

Finding available software
Software Update found the following new or updated software:
* Label: Command Line Tools for Xcode-11.2
	Title: Command Line Tools for Xcode, Version: 11.2, Size: 224942K, Recommended: YES,
* Label: Command Line Tools for Xcode-11.3
	Title: Command Line Tools for Xcode, Version: 11.3, Size: 224878K, Recommended: YES,

softwareupdate -i expect "Command Line Tools for Xcode-11.2" not "Label: Command Line Tools for Xcode-11.2". Support for Mojave/High Sierra is preserved, since the added sed pipe won't change output without "Label: ".

[herbota]

I also encountered this issue when installing Command Line Tools for Xcode in Catalina. This change fixed that.