fix lint errors revealed by pycodestyle 2.11

When performing isinstance checks, an identity comparison is
automatically done, but we don't use isinstance here because we need
strict identity equality *without allowing subtypes*.

Comparing type() == type() is a value comparison, but could produce
effectively the same results as an identity comparison, usually, despite
being semantically off. pycodestyle learned to detect this and warn you
to do strict identity comparison.

(cherry picked from commit d461536)

mesonbuild/coredata.py

@@ -807,7 +807,7 @@ def update_project_options(self, options: 'MutableKeyedOptionDictType') -> None:
                 continue
 
             oldval = self.options[key]
-            if type(oldval) != type(value):
+            if type(oldval) is not type(value):
                 self.options[key] = value
             elif oldval.choices != value.choices:
                 # If the choices have changed, use the new value, but attempt

mesonbuild/interpreterbase/baseobjects.py

@@ -119,12 +119,12 @@ def op_equals(self, other: TYPE_var) -> bool:
         # We use `type(...) == type(...)` here to enforce an *exact* match for comparison. We
         # don't want comparisons to be possible where `isinstance(derived_obj, type(base_obj))`
         # would pass because this comparison must never be true: `derived_obj == base_obj`
-        if type(self) != type(other):
+        if type(self) is not type(other):
             self._throw_comp_exception(other, '==')
         return self == other
 
     def op_not_equals(self, other: TYPE_var) -> bool:
-        if type(self) != type(other):
+        if type(self) is not type(other):
             self._throw_comp_exception(other, '!=')
         return self != other
 
@@ -157,12 +157,12 @@ def display_name(self) -> str:
     # Override default comparison operators for the held object
     def op_equals(self, other: TYPE_var) -> bool:
         # See the comment from InterpreterObject why we are using `type()` here.
-        if type(self.held_object) != type(other):
+        if type(self.held_object) is not type(other):
             self._throw_comp_exception(other, '==')
         return self.held_object == other
 
     def op_not_equals(self, other: TYPE_var) -> bool:
-        if type(self.held_object) != type(other):
+        if type(self.held_object) is not type(other):
             self._throw_comp_exception(other, '!=')
         return self.held_object != other