README: master -> main

Author: gshackles

README.md

@@ -2,7 +2,7 @@
 
 FluentLayout provides an easy, fluent API for creating constraint-based layouts in Xamarin.iOS.
 
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+[![Build Status](https://app.bitrise.io/app/3584ad3a37e4084c/status.svg?token=nxuhVtDms232YxvcvYIW0w&branch=main)](https://app.bitrise.io/app/3584ad3a37e4084c)
 
 ## How To Use
 
@@ -46,4 +46,4 @@ When using the `VerticalStackPanelConstraints` helper each constraint added will
 
 - `containerId` will be the container's `AccessibilityIdentifier` if one is set, and `VerticalStackPanel` if not
 - `viewId` will be the subview's `AccessibilityIdentifier` if one is set, and the subview's index in the array if not
-- `constraintDescription` will be based on the constraint itself, such as `Bottom`, `Top`, `Width`, etc.
+- `constraintDescription` will be based on the constraint itself, such as `Bottom`, `Top`, `Width`, etc.