Don't allow to stake amounts below the min stake

[cygnusv]

There are reports from stakers with UI failures when the stake amount is below or equal to the min stake (40K T). The UI should only allow to stake amounts that are greater than the min.

For reference, the smart contract checks the amount is strictly greater:
require(amount > minTStakeAmount, "Amount is less than minimum");

[cygnusv]

As a workaround, the min stake was changed by the Council to 39,999.999999999999999999, so stakers with exactly 40k can stake, but the UI still shouldn't allow to input below that amount