docs: update readme post-repovation

[mymphe]

This PR updates README after repovation: removes disclaimer and updates bug bounty.

MERGE AFTER BUG BOUNTY UPDATE!

Problem

After repovation is done, the disclaimer will be outdated and bug bounty will not cover old repo.

Solution

Updates the readme.

[github-actions]

Hardhat Unit Tests Coverage Summary

Filename                                                       Stmts    Miss  Cover    Missing
-----------------------------------------------------------  -------  ------  -------  ---------
contracts/0.4.24/Lido.sol                                        212       0  100.00%
contracts/0.4.24/StETH.sol                                        72       0  100.00%
contracts/0.4.24/StETHPermit.sol                                  15       0  100.00%
contracts/0.4.24/lib/Packed64x4.sol                                5       0  100.00%
contracts/0.4.24/lib/SigningKeys.sol                              36       0  100.00%
contracts/0.4.24/lib/StakeLimitUtils.sol                          37       0  100.00%
contracts/0.4.24/nos/NodeOperatorsRegistry.sol                   485       0  100.00%
contracts/0.4.24/oracle/LegacyOracle.sol                          72       0  100.00%
contracts/0.4.24/utils/Pausable.sol                                9       0  100.00%
contracts/0.4.24/utils/Versioned.sol                               5       0  100.00%
contracts/0.6.12/WstETH.sol                                       17       0  100.00%
contracts/0.8.4/WithdrawalsManagerProxy.sol                       61       0  100.00%
contracts/0.8.9/BeaconChainDepositor.sol                          21       2  90.48%   48, 51
contracts/0.8.9/Burner.sol                                        71       0  100.00%
contracts/0.8.9/DepositSecurityModule.sol                        104       0  100.00%
contracts/0.8.9/EIP712StETH.sol                                   16       0  100.00%
contracts/0.8.9/LidoExecutionLayerRewardsVault.sol                16       0  100.00%
contracts/0.8.9/LidoLocator.sol                                   18       0  100.00%
contracts/0.8.9/OracleDaemonConfig.sol                            28       0  100.00%
contracts/0.8.9/StakingRouter.sol                                303       0  100.00%
contracts/0.8.9/WithdrawalQueue.sol                               88       0  100.00%
contracts/0.8.9/WithdrawalQueueBase.sol                          146       0  100.00%
contracts/0.8.9/WithdrawalQueueERC721.sol                         89       0  100.00%
contracts/0.8.9/WithdrawalVault.sol                               21       0  100.00%
contracts/0.8.9/lib/Math.sol                                       4       0  100.00%
contracts/0.8.9/lib/PositiveTokenRebaseLimiter.sol                22       0  100.00%
contracts/0.8.9/lib/UnstructuredRefStorage.sol                     2       0  100.00%
contracts/0.8.9/oracle/AccountingOracle.sol                      171       1  99.42%   723
contracts/0.8.9/oracle/BaseOracle.sol                             89       1  98.88%   397
contracts/0.8.9/oracle/HashConsensus.sol                         263       1  99.62%   1005
contracts/0.8.9/oracle/ValidatorsExitBusOracle.sol                91      91  0.00%    96-461
contracts/0.8.9/proxy/OssifiableProxy.sol                         17       0  100.00%
contracts/0.8.9/sanity_checks/OracleReportSanityChecker.sol      171       0  100.00%
contracts/0.8.9/utils/DummyEmptyContract.sol                       0       0  100.00%
contracts/0.8.9/utils/PausableUntil.sol                           31       0  100.00%
contracts/0.8.9/utils/Versioned.sol                               11       0  100.00%
contracts/0.8.9/utils/access/AccessControl.sol                    23       0  100.00%
contracts/0.8.9/utils/access/AccessControlEnumerable.sol           9       0  100.00%
TOTAL                                                           2851      96  96.63%

Diff against master

Filename                                                       Stmts    Miss  Cover
-----------------------------------------------------------  -------  ------  --------
contracts/0.8.9/sanity_checks/OracleReportSanityChecker.sol      -54       0  +100.00%
TOTAL                                                            -54       0  -0.03%

Results for commit: f134950

Minimum allowed coverage is 95%

♻️ This comment has been updated with latest results

[tamtamchik]

Closed. Ported to lidofinance/lido-dao#864