Fetch the minimum active nomination from on-chain

[alfarok]

Via #4120

Automatically fetch the minimum active nomination from the chain and display it in ./docs/general/getting-started.md?

It adds a lot of value to this page and ensures that the reader is not misled into believing 10 DOT is enough to become an active nominator and earn rewards.

[DrW3RK]

@alfarok Looks like we can fetch this value on-chain after this PR paritytech/substrate#12889

[alfarok]

@DrW3RK Awesome, that should make life for this task easier! How long does it normally take for these changes to make their way over to Polkadot-JS or is this something we should request on GitHub now that it is available?

[alfarok]

I replaced all the hard-coded values in Getting-Started in #4214 but still waiting for this specific value to be available via Polkadot-JS. I also added this content to the Kusama-Getting-Started doc.

[DrW3RK]

It will be available after this runtime upgrade makes its way to the chain https://github.com/paritytech/polkadot/releases/tag/v0.9.36

[DrW3RK]

Available on chain now

[alfarok]

Nice! We should be able to use the RPC component w/ the HumanReadable filter to add this info to the wiki. Let me know if you want me to add it. From the initial linked PR it looks like this info would go on the getting started page?

[alfarok]

Addressed w/ #4487