revert irrelevant changes

Author: mmatera

mathics/builtin/arithfns/basic.py

@@ -535,8 +535,6 @@ class Power(BinaryOperator, MPMathFunction):
     rules = {
         "Power[]": "1",
         "Power[x_]": "x",
-        "Power[I,-1]": "-I",
-        "Power[-1, 1/2]": "I",
     }
 
     summary_text = "exponentiate"

test/builtin/arithmetic/test_basic.py

@@ -153,8 +153,8 @@ def test_multiply(str_expr, str_expected, msg):
         ("a  b  DirectedInfinity[q]", "a b (q Infinity)", ""),
         # Failing tests
         # Problem with formatting. Parenthezise are missing...
-        ("a  b  DirectedInfinity[-I]", "a b (-I Infinity)", ""),
-        ("a  b  DirectedInfinity[-3]", "a b (-Infinity)", ""),
+        #        ("a  b  DirectedInfinity[-I]", "a b (-I Infinity)",  ""),
+        #        ("a  b  DirectedInfinity[-3]", "a b (-Infinity)",  ""),
     ],
 )
 def test_directed_infinity_precedence(str_expr, str_expected, msg):