test(frontend): run only in multi instead of changing config

as test runs two times, once in mono, and once in multi, we can just
skip the test unless we are in multi

frontends/concrete-python/tests/execution/test_tfhers.py

@@ -112,10 +112,10 @@ def test_tfhers_conversion_binary_encrypted(
     """
 
     parameter_encryption_statuses = helpers.generate_encryption_statuses(parameters)
-    # tfhers int works with multi-parameters only
-    configuration = helpers.configuration().fork(
-        parameter_selection_strategy=fhe.ParameterSelectionStrategy.MULTI
-    )
+
+    # Only valid when running in multi
+    if helpers.configuration().parameter_selection_strategy != fhe.ParameterSelectionStrategy.MULTI:
+        return
 
     dtype = parameterize_partial_dtype(dtype)
 
@@ -128,7 +128,7 @@ def test_tfhers_conversion_binary_encrypted(
         tuple(tfhers.TFHERSInteger(dtype, arg) for arg in inpt)
         for inpt in helpers.generate_inputset(parameters)
     ]
-    circuit = compiler.compile(inputset, configuration)
+    circuit = compiler.compile(inputset, helpers.configuration())
 
     assert is_input_and_output_tfhers(
         circuit,
@@ -231,10 +231,10 @@ def test_tfhers_conversion_one_encrypted_one_native(
     """
 
     parameter_encryption_statuses = helpers.generate_encryption_statuses(parameters)
-    # tfhers int works with multi-parameters only
-    configuration = helpers.configuration().fork(
-        parameter_selection_strategy=fhe.ParameterSelectionStrategy.MULTI
-    )
+
+    # Only valid when running in multi
+    if helpers.configuration().parameter_selection_strategy != fhe.ParameterSelectionStrategy.MULTI:
+        return
 
     dtype = parameterize_partial_dtype(dtype)
 
@@ -247,7 +247,7 @@ def test_tfhers_conversion_one_encrypted_one_native(
         (tfhers.TFHERSInteger(dtype, inpt[0]), inpt[1])
         for inpt in helpers.generate_inputset(parameters)
     ]
-    circuit = compiler.compile(inputset, configuration)
+    circuit = compiler.compile(inputset, helpers.configuration())
 
     assert is_input_and_output_tfhers(
         circuit,
@@ -519,8 +519,10 @@ def test_tfhers_conversion_without_multi(function, parameters, parameter_strateg
     """
 
     parameter_encryption_statuses = helpers.generate_encryption_statuses(parameters)
-    # tfhers int works with multi-parameters only
-    configuration = helpers.configuration().fork(parameter_selection_strategy=parameter_strategy)
+
+    # Only valid when running in multi
+    if helpers.configuration().parameter_selection_strategy != fhe.ParameterSelectionStrategy.MULTI:
+        return
 
     dtype = parameterize_partial_dtype(tfhers.uint16_2_2)
 
@@ -534,7 +536,7 @@ def test_tfhers_conversion_without_multi(function, parameters, parameter_strateg
         for inpt in helpers.generate_inputset(parameters)
     ]
     with pytest.raises(RuntimeError, match=f"Can't use tfhers integers with {parameter_strategy}"):
-        compiler.compile(inputset, configuration)
+        compiler.compile(inputset, helpers.configuration())
 
 
 def test_tfhers_circuit_eval():