fix:3058: filter 0 calls per period weeklyreports

Description

Filter WeeklyReport where number of tracker calls would display "0", as observed by Raj during validation

Screenshots

Tests

If there isn't any tracking data in AdvancedPrivacy this test: https://gitlab.e.foundation/e/os/advanced-privacy/-/quality/test_cases/32 shouldn't show any report.

Issues

https://gitlab.e.foundation/e/os/backlog/-/issues/3058#note_670444 https://gitlab.e.foundation/e/os/backlog/-/issues/3236

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