Fix for integer overflow of counter value if its too large (sonic-net#3596)

What I did
Changed the data type casting to float if count coming is too large or in scientific notation .

How I did it
made it float then type cast to int for display purpose

How to verify it
Manually passed big value and see the count output if it breaks or works

Author: harjotsinghpawra

utilities_common/portstat.py

@@ -229,7 +229,7 @@ def get_counters(port):
                     if counter_name not in fvs:
                         fields[pos] = STATUS_NA
                     elif fields[pos] != STATUS_NA:
-                        fields[pos] = str(int(fields[pos]) + int(fvs[counter_name]))
+                        fields[pos] = str(int(fields[pos]) + int(float(fvs[counter_name])))
 
             cntr = NStats._make(fields)._asdict()
             return cntr