Update docs about Countly being shut down

[BigLep]

This is in support of the Countly account shutdown discussed in #133

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[SgtPooki]

we should wait to merge this until it's true

[BigLep]

we should wait to merge this until it's true

@SgtPooki : I update the text to specify the date for which this will be true. Given this, are you ok merging it? My push to merge so we have less to worry about a couple of weeks from now.

Confirmation that the account will be shutoff by 2024-02-18 is in https://filecoinproject.slack.com/archives/C03KQ8MC62Y/p1706641447466369?thread_ts=1705585701.925229&cid=C03KQ8MC62Y

[SgtPooki]

Eh, im fine with merging like it is, since its only 2 weeks out