UserPoolIdentityProvider was added in Oct 2019, official docs.

Your CloudFormation would then look something like

CognitoUserPoolIdentityProvider:
  Type: AWS::Cognito::UserPoolIdentityProvider
  Properties: 
    ProviderName: Google
    AttributeMapping:
      email: emailAddress
    ProviderDetails:
      client_id: <yourclientid>.apps.googleusercontent.com
      client_secret: <yourclientsecret>
      authorize_scopes: email openid
    ProviderType: Google
    UserPoolId: 
      Ref: CognitoUserPool

It seems a lot of Cognito details are not supported within Cloudformation as of right now, but there are ways to achieve what you want after the stack spins up, e.g. using Lambdas.

See the following answers:

Cannot set a property of cognito userpool client via cloudformation

Cloudformation Cognito - how to setup App Client Settings, Domain, and Federated Identities via SAM template

You can achieve this using Lambda function as custom Cloudformation resources. I have made custom resources to allow creation of user pool domain, client settings and Identity providers on this repo

You will have somethings like this for creating identity provider, for example Facebook

FacebookIdp:
  Type: 'Custom::${self:service}-${self:provider.stage}-CUPIdentityProvider'
  DependsOn:
    - CFNSendResponseLambdaFunction
    - CUPIdentityProviderLambdaFunction
  Properties:
    ServiceToken:
      Fn::GetAtt: [CUPIdentityProviderLambdaFunction, Arn]
    UserPoolId:
      Ref: AppUserPool
    ProviderName: Facebook
    ProviderType: Facebook
    Client_id: 'YourFacebookAppID'
    Client_secret: 'YourFacebookAppSecert'
    Authorize_scopes: 'public_profile,email'

And then enable that identity provider on the user pool client settings

AppUserPoolClientSettings:
  Type: 'Custom::${self:service}-${self:provider.stage}-CUPClientSettings'
  DependsOn:
    - CFNSendResponseLambdaFunction
    - CUPClientSettingsLambdaFunction
    - FacebookIdp
  Properties:
    ServiceToken:
      Fn::GetAtt: [ CUPClientSettingsLambdaFunction, Arn]
    UserPoolId: 
      Ref: AppUserPool
    UserPoolClientId: 
      Ref: AppUserPoolClient
    SupportedIdentityProviders:
      - COGNITO
      - Facebook
    CallbackURL: 'https://www.yourdomain.com/callback' ##Replace this with your app callback url
    LogoutURL: 'https://www.yourdomain.com/logout' ##Replace this with your app logout url
    AllowedOAuthFlowsUserPoolClient: true
    AllowedOAuthFlows:
      - code
    AllowedOAuthScopes:
      - openid

Note that this repo is built using Serverless framework, if you wish to build this with pure cloudformation stacks, use the code on file CUPIdentityProvider.js to make your own custom resource.