package/jack2: fix build with python 3.12

package/jack2: fix build with python 3.12

Fix the following build failure with python 3.12 (which removed imp
module):

Traceback (most recent call last):
  File "/home/autobuild/autobuild/instance-7/output-1/build/jack2-1.9.22/./waf", line 166, in <module>
    from waflib import Scripting
  File "/home/autobuild/autobuild/instance-7/output-1/build/jack2-1.9.22/waflib/Scripting.py", line 10, in <module>
    from waflib import Utils, Configure, Logs, Options, ConfigSet, Context, Errors, Build, Node
  File "/home/autobuild/autobuild/instance-7/output-1/build/jack2-1.9.22/waflib/Configure.py", line 16, in <module>
    from waflib import ConfigSet, Utils, Options, Logs, Context, Build, Errors
  File "/home/autobuild/autobuild/instance-7/output-1/build/jack2-1.9.22/waflib/Options.py", line 14, in <module>
    from waflib import Logs, Utils, Context, Errors
  File "/home/autobuild/autobuild/instance-7/output-1/build/jack2-1.9.22/waflib/Context.py", line 9, in <module>
    import os, re, imp, sys
ModuleNotFoundError: No module named 'imp'

Fixes: 36e635d2d5c0166476858aa239ccbe78e8f2af14
 - http://autobuild.buildroot.org/results/1bfe34e10ffdab80647ac01863165e93bcc9b0d8

Signed-off-by: Fabrice Fontaine <[email protected]>
Signed-off-by: Thomas Petazzoni <[email protected]>