HIP-1215 Add integration tests for the new schedule functions

[bilyana-gospodinova]

Description:
This PR adds integration tests for the new functions provided in the Hedera Schedule service:

• IHederaScheduleService.scheduleCall
• IHederaScheduleService.scheduleCallWithPayer
• IHederaScheduleService.executeCallOnPayerSignature
• IHederaScheduleService.deleteSchedule
• IHederaScheduleService.hasScheduleCapacity

An abstract class (AbstractContractCallScheduleTest) is created in this PR in order to contain some common methods for the schedule tests.

Fixes #11651

[lfdt-bot]

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[codacy-production]

Coverage summary from Codacy

See diff coverage on Codacy

Coverage variation	Diff coverage
❌ -31.93% (target: -1.00%)	✅ 40.00%

Coverage variation details

	Coverable lines	Covered lines	Coverage
Common ancestor commit (1991e40)	36936	33645	91.09%
Head commit (689c17e)	61748 (+24812)	36528 (+2883)	59.16% (-31.93%)

Coverage variation is the difference between the coverage for the head and common ancestor commits of the pull request branch: <coverage of head commit> - <coverage of common ancestor commit>

Diff coverage details

	Coverable lines	Covered lines	Diff coverage
Pull request (#12257)	5	2	40.00%

Diff coverage is the percentage of lines that are covered by tests out of the coverable lines that the pull request added or modified: <covered lines added or modified>/<coverable lines added or modified> * 100%

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[steven-sheehy]

0.67 proto has been merged

[sdimitrov9]

LGTM