Revert "Fix gauge of CTM tensors by the maximal value of the tensor"

This reverts commit fbaa5e1.

Author: JanLuca

varipeps/ctmrg/absorption.py

@@ -96,12 +96,7 @@ def _get_ctmrg_1x2_structure(
 
 def _post_process_CTM_tensors(a: jnp.ndarray, config: VariPEPS_Config) -> jnp.ndarray:
     a = a / jnp.linalg.norm(a)
-
-    idx = jnp.argmax(jnp.abs(a))
-    max_val = a.flatten()[idx]
-    phase = max_val / jnp.abs(max_val)
-
-    return a * phase.conj()
+    return a
 
 
 def do_left_absorption(