TST: Adapt to __array__(copy=True)

[thalassemia]

Fixes test failures pointed out in #20510 (comment) due to numpy enforcing __array__(copy=True) in numpy/numpy#26215.

[tylerjereddy]

Indeed, the patch below the fold does the trick for me locally, with both runtime versions of NumPy

--- a/scipy/optimize/_nonlin.py
+++ b/scipy/optimize/_nonlin.py
@@ -13,6 +13,7 @@ import scipy.sparse.linalg
 import scipy.sparse
 from scipy.linalg import get_blas_funcs
 from scipy._lib._util import getfullargspec_no_self as _getfullargspec
+from scipy._lib._util import copy_if_needed
 from ._linesearch import scalar_search_wolfe1, scalar_search_armijo
 
 
@@ -701,7 +702,7 @@ class LowRankMatrix:
 
     def collapse(self):
         """Collapse the low-rank matrix to a full-rank one."""
-        self.collapsed = np.array(self, copy=None)
+        self.collapsed = np.array(self, copy=copy_if_needed)
         self.cs = None
         self.ds = None
         self.alpha = None