support/testing: TestPythonPy3SciPy: needs a toolchain with Fortran support

Switch to the Bootlin bleeding-edge toolchain since stable toolchain no
longer provide Fortran support since 2024.05-1 release [1].

The Fortran support is now optional in toolchain-builder tool and
only enabled for bleeding-edge toolchains [2].

[1] https://gitlab.com/buildroot.org/buildroot/-/commit/d3ad58dce9cafccb22d782e56677e060d5eb5a52#428f572a75eed97c0a70da290028c0efb4224a79_545_536
[2] https://gitlab.com/buildroot.org/toolchains-builder/-/commit/a178b246259d92e23679b777fa3d6c166cc424d5

Fixes: (partially)
https://gitlab.com/buildroot.org/buildroot/-/jobs/8199992675

Signed-off-by: Romain Naour <romain.naour@smile.fr>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>

support/testing/tests/package/test_python_scipy.py

@@ -5,8 +5,15 @@ from tests.package.test_python import TestPythonPackageBase
 
 class TestPythonPy3SciPy(TestPythonPackageBase):
     __test__ = True
-    config = TestPythonPackageBase.config + \
+    # Need to use a different toolchain than the default due to
+    # missing Fortran support (required by python-scipy) in Bootlin
+    # stable toolchains 2024.05
+    config = \
         """
+        BR2_arm=y
+        BR2_TOOLCHAIN_EXTERNAL=y
+        BR2_TOOLCHAIN_EXTERNAL_BOOTLIN=y
+        BR2_TOOLCHAIN_EXTERNAL_BOOTLIN_ARMV5_EABI_GLIBC_BLEEDING_EDGE=y
         BR2_PACKAGE_PYTHON3=y
         BR2_PACKAGE_PYTHON_SCIPY=y
         BR2_TARGET_ROOTFS_EXT2=y