Revert "Update pytensor/link/pytorch/dispatch/slinalg.py"

This reverts commit 0dc65e2.

Author: twaclaw

Diff for: pytensor/link/pytorch/dispatch/slinalg.py

@@ -64,7 +64,7 @@ def solve_triangular(A, b):
         else:
             A_p = A
 
-        b_p = pt.atleast_2d(b, left=False)
+        b_p = b
         if b.ndim == 1:
             b_p = b[:, None]