[variant.variant.general] Replace "instance" with "object"

Author: frederick-vs-ja

source/utilities.tex

@@ -5723,9 +5723,9 @@
 \end{codeblock}
 
 \pnum
-Any instance of \tcode{variant} at any given time either holds a value
+Any object of \tcode{variant} at any given time either holds a value
 of one of its alternative types or holds no value.
-When an instance of \tcode{variant} holds a value of alternative type \tcode{T},
+When an object of \tcode{variant} holds a value of alternative type \tcode{T},
 it means that a value of type \tcode{T}, referred to as the \tcode{variant}
 object's \defnx{contained value}{contained value!\idxcode{variant}},
 is nested within\iref{intro.object} the