Switch Substrate dependency import to polkadot release branches

[haerdib]

We keep running into problems due to substrate versions dependencies being updated.

We have the following options:

1. master branch (how it's currently done)
   • (+) Would theoretically give us the flexibility to update via cargo update --precise xxx-commit. Not possible currently due to the necessity of specifying the dev version (4.0.0-dev))
   • (-) Due to the versioning, we are regularly forced to update (worker can not be built anymore).
2. monthly tags
   • (-) the node would need to follow suit
3. polkadot branches (like parachain)
   • (+) we could follow the version of our parachain
4. specific commits
   • (-) the node would need to follow suit

[clangenb]

I have had enough of the suddenly breaking builds by just referencing the master branch. If these breakages occur in the wrong moment, they pose a serious hazard to potential deadlines and planing.

It seems that the polkadot repository determines what other options we have. I will start by excluding options systematically not possible:

3. monthly-tags: not possible as the polkadot repository does not have this. The only tags contained there are release-v0.9.18 etc., which references substrate's polkadot-v0.9.18 branch.
4. specific commits: This is not possible because the polkadot-deps would still reference substrate with branch = master. Cargo cannot resolve the dependency as the same even if the referenced commit exists in master branch. Hence, we get duplicate imports.

Therefore, this leaves only the status quo or using polkadot-release branches.

[haerdib]

Ajuna has the problem that they depend on the orml-pallets, which also points to polkadot releases.

[brenzi]

polkadot releases could work well, I think because that's how parity solves the same problem on their side

[gaudenzkessler]

Rebase of teeracle.

[haerdib]

So this task now includes the bump of the worker and all the dependent repositories, excluding solochain and parachain, which are tasked in integritee-network/parachain#82

[echevrier]

The latest substrate polkadot branch ( polkadot-v0.9.18) is behind the current substrate version and does not have the fix for the full_crypto std bug (paritytech/substrate#11005) -> worker, sgx-runtime, teeracle will not compile.
@brenzi and @clangenb : Should we wait for the next polkadot release ? Note: Integritee node and pallets are already "downgraded" to polkadot-v0.9.18

[clangenb]

v0.9.19 is out and would include the fix we need. 👍