iOS: Resolve a build warning for 32bit devices (#19416)

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This PR resolves a warning `Implicit conversion loses floating-point precision: 'double' to 'CGFloat' (aka 'float')` when building not only this library **but also apps** for 32bit devices since it's declared in public header file.
Pull Request resolved: #19416

Differential Revision: D14206633

Pulled By: cpojer

fbshipit-source-id: a65a4774235fa7fb24fac2f9bf7e51ba2a027377

Libraries/NativeAnimation/Drivers/RCTAnimationDriver.h

@@ -10,7 +10,7 @@
 
 #import <React/RCTBridgeModule.h>
 
-static CGFloat RCTSingleFrameInterval = 1.0 / 60.0;
+static CGFloat RCTSingleFrameInterval = (CGFloat)(1.0 / 60.0);
 
 @class RCTValueAnimatedNode;