Create more E2E test scenarios for task scheduling

[rockbmb]

#194 created an E2E test suite for the scheduler mechanism, but some things are missing, namely:

• a check that scheduled task retry mechanism is working
• a check that cancelling a scheduled task's retry configuration also works

[rockbmb]

@xlc could you elaborate on what you said about non-inline calls having scheduling issues in the Collectives parachain?

I was unaware there was such an issue.

[xlc]

polkadot-fellows/runtimes#614

TLDR; the weight for scheduler pallet was wrong and causing all non-inline scheduling fail on polkadot collectives chain