[pygobject] Revert "setup.py: Also set setup_requires to require pycairo"

[Christoph Reiter <creiter src gnome org>]

commit 2e30c7fbfcb579efb2ff7134979f169f673ac285
Author: Christoph Reiter <creiter src gnome org>
Date:   Mon Dec 11 18:32:16 2017 +0100

    Revert "setup.py: Also set setup_requires to require pycairo"
    
    This reverts commit bab1cb0d98e4a6219332394161dbf07aafa0c615.
    
    pycairo gets installed under /tmp as an .egg this way, and that doesn't help us
    with finding the C headers.

 setup.py |    4 ----
 1 files changed, 0 insertions(+), 4 deletions(-)
---
diff --git a/setup.py b/setup.py
index dbeed65..95669db 100644
--- a/setup.py
+++ b/setup.py
@@ -380,10 +380,6 @@ def main():
             "pycairo>=%s" % get_version_requirement(
                 script_dir, get_pycairo_pkg_config_name()),
         ],
-        setup_requires=[
-            "pycairo>=%s" % get_version_requirement(
-                script_dir, get_pycairo_pkg_config_name()),
-        ],
     )