pkgs/sagemath-standard: Make sagemath-environment a build-requirement instead of manipulating sys.path

Author: Matthias Koeppe

pkgs/sagemath-standard/pyproject.toml.m4

@@ -10,6 +10,7 @@ requires = [
         setuptools \
         wheel          \
         sage_setup     \
+        sagemath_environment \
         cypari         \
         cysignals      \
         cython         \

pkgs/sagemath-standard/setup.py

@@ -28,9 +28,6 @@
 ### Set source directory
 #########################################################
 
-# PEP 517 builds do not have . in sys.path
-sys.path.insert(0, os.path.dirname(__file__))
-
 import sage.env
 sage.env.SAGE_SRC = os.getcwd()
 from sage.env import *