[SCB-940] move float type test case from demo to integration-test

[heyile]

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[liubao68]

This PR conflicts with previous merged one. Please rebase and fix it.

[heyile]

This PR conflicts with previous merged one. Please rebase and fix it.

ok, i will fix it soon

[coveralls]

Coverage increased (+0.08%) to 86.286% when pulling 402ed43 on heyile:it-float into 6aadae0 on apache:master.