utils: stop rewriting shbang lines in setup script

The python setup tools script is set to rewrite the shbang line of
scripts installed in ${PREFIX}/bin/ if the PYTHON environment variable
is set. Unfortunately, this (a) only covers the aa-easyprof script
as the rest are installed in ${PREFIX}/sbin/, and (b) we've deprecated
python 2 support, and hardcoded python3 as the interpreter for all of
the python scripts in the utils/ directory.

The only use for this feature would be if for some reason the utils did
not work properly with the default python3 interpreter and a specific
version was needed to be set, but I don't think that warrants keeping
the extra bit of code complexity around (and indeed, the snippet that
does this is forcibly disabled in Debian/Ubuntu).

Therefore, drop the shbang rewriting entirely.

Signed-off-by: Steve Beattie <steve@nxnw.org>
Acked-by: John Johansen <john.johansen@canonical.com>

utils/python-tools-setup.py

@@ -41,14 +41,7 @@ class Install(_install, object):
         self.mkpath(prefix + os.path.dirname(scripts[0]))
         for s in scripts:
             f = prefix + s
-            # If we have a defined python version, use it instead of the system
-            # default
-            if 'PYTHON' in os.environ:
-                lines = open(os.path.basename(s)).readlines()
-                lines[0] = '#! /usr/bin/env %s\n' % os.environ['PYTHON']
-                open(f, 'w').write("".join(lines))
-            else:
-                self.copy_file(os.path.basename(s), f)
+            self.copy_file(os.path.basename(s), f)
 
         configs = ['easyprof/easyprof.conf']
         self.mkpath(prefix + "/etc/apparmor")