Remove duplicate declaration.

Process.h

@@ -158,8 +158,6 @@ typedef struct ProcessClass_ {
 #define ONE_DECIMAL_M (ONE_DECIMAL_K * ONE_DECIMAL_K)
 #define ONE_DECIMAL_G (ONE_DECIMAL_M * ONE_DECIMAL_K)
 
-extern char Process_pidFormat[20];
-
 void Process_setupColumnWidths();
 
 void Process_humanNumber(RichString* str, unsigned long number, bool coloring);