Add torch jit ignore decorator to Lightning properties

[ananthsub]

What does this PR do?

This PyTorch PR adds support to TorchScript for module properties, and as a result, these module properties in Lightning will no longer compile because they use unsupported features in their properties (that are now being compiled)

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[Borda]

@ananthsub seems all tests are failing, mind have a look?
E RuntimeError: Argument to @torch.jit.ignore must be a bool or a function but got <property object at 0x7f7506a384a8>

[thomasjo]

@Borda The upstream PR hasn't been merged yet. This PR cannot be merged before the upstream PR is merged and available in a stable PyTorch release (possibly 1.7).

[Borda]

@Borda The upstream PR hasn't been merged yet. This PR cannot be merged before the upstream PR is merged and available in a stable PyTorch release (possibly 1.7).

well, even 1.7 is out we need to maintain compatibility for pt<1.7 so we cannot merge it until this change is compatible also with older PT versions...

[Borda]

we need to maintain compatibility with all supported PT versions, and this is valid only for the upcoming PT 1.7

[mergify]

This pull request is now in conflict... :(

[ananthsub]

this was handled by #3541