Fix repeat operationids in OpenAPI Schema

[dongfangtianyu]

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Description

on Open API3.0 ,Operations must have unique operationIds. refs ##6549 Maybe Forget action decorator

This will result in the same Operations ID：

class ExampleGenericViewSet(GenericViewSet):
    @action(detail=False)
    def new(self, *args, **kwargs):
        pass

    @action(detail=False)
    def old(self, *args, **kwargs):
        pass

[carltongibson]

Merged in 637a263. Thank again @dongfangtianyu!