generators: get rid of deprecation warning nicer way

datetime.datetime.now(datetime.timezone.utc) should work on Python 3.10
and newer.

generate-cpu-cores-table.py

@@ -1,6 +1,6 @@
 #!/usr/bin/env python3
 
-from datetime import datetime
+from datetime import datetime, timezone
 from jinja2 import Environment, FileSystemLoader
 
 import tables
@@ -42,7 +42,8 @@ def generate_html_file(cpu_cores):
     template = env.get_template("arm-cpu-cores.html.j2")
 
     output = template.render(
-        generate_time=datetime.strftime(datetime.utcnow(), "%d %B %Y %H:%M"),
+        generate_time=datetime.strftime(datetime.now(timezone.utc),
+                                        "%d %B %Y %H:%M"),
         cpu_cores=cpu_cores,
     )
     print(output)

generate.py

@@ -1,6 +1,6 @@
 #!/usr/bin/env python3
 
-from datetime import datetime
+from datetime import datetime, timezone
 from jinja2 import Environment, FileSystemLoader
 
 import tables
@@ -118,7 +118,8 @@ def generate_html_file(socs, cpu_features, cpu_cores):
     template = env.get_template("arm-socs.html.j2")
 
     output = template.render(
-        generate_time=datetime.strftime(datetime.utcnow(), "%d %B %Y %H:%M"),
+        generate_time=datetime.strftime(datetime.now(timezone.utc),
+                                        "%d %B %Y %H:%M"),
         socs=socs,
         cpu_features=cpu_features,
         cpu_cores=cpu_cores,