mobx@6.3.3

Patch Changes

• d78a1592 #2902 Thanks @z3rog! - chore: observable use internal constants

• db21d85f #2998 Thanks @urugator! - trace(): log when computed becomes suspended
  requiresReaction warns instead of throwing

• b9fa119c #3056 Thanks @upsuper! - Create WHEN_TIMEOUT error earlier to capture useful stack

• 99491ec2 #2972 Thanks @kk-gjyang! - Polyfill Object.is for old/unsupported browsers

• 0d28db8a #2927 Thanks @upsuper! - Give proper typing to opts.equals of reaction

• c6dc925c #2985 Thanks @fecqs! - Remove duplicate global property check