Update shebang to python3

Python version 3.7 or higher required due to asyncio

analyze_wotb_replays.py

@@ -1,4 +1,5 @@
-#!/usr/bin/env python3.8
+#!/usr/bin/env python3
+## PYTHON VERSION MUST BE 3.7 OR HIGHER
 
 # Script Analyze WoT Blitz replays
 

blitzutils.py

@@ -1,4 +1,5 @@
-#!/usr/bin/env python3.8
+#!/usr/bin/env python3
+## PYTHON VERSION MUST BE 3.7 OR HIGHER
 
 import sys, os, json, time,  base64, urllib, inspect, hashlib, re, string, random
 import asyncio, aiofiles, aiohttp, aiosqlite, lxml

extract_tankopedia.py

@@ -1,4 +1,5 @@
-#!/usr/bin/env python3.8
+#!/usr/bin/env python3
+## PYTHON VERSION MUST BE 3.7 OR HIGHER
 
 # Extract tankopedia data in WG API JSON format from Blitz app files (Android APK unzipped)
 

upload_wotb_replays.py

@@ -1,4 +1,5 @@
-#!/usr/bin/env python3.8
+#!/usr/bin/env python3
+## PYTHON VERSION MUST BE 3.7 OR HIGHER
 
 import json, argparse, inspect, sys, os, io, base64, aiohttp, urllib, asyncio, aiofiles, aioconsole
 import logging, re, concurrent.futures, configparser, motor.motor_asyncio, ssl, zipfile