software/beremiz-runtime: Downgrade pip, wheel and setuptools

This SR is kept separate because it is not part of current tests.

software/beremiz-runtime/software.cfg

@@ -11,6 +11,9 @@ extends =
   ../../stack/monitor/buildout.cfg
   ../../stack/slapos.cfg
 
+# Python2 versions for buildout (keep last)
+  ../../stack/slapos-py2.cfg
+
 parts =
   beremiz-source
   slapos-cookbook
@@ -19,9 +22,6 @@ parts =
   matiec
   open62541
 
-[python]
-part = python2.7
-
 [gcc]
 # we want this SR to use a fixed gcc (so that we have the same gcc as open62541 component)
 max_version = 0