Update Base64.sol

Author: Amxx

contracts/utils/Base64.sol

@@ -185,24 +185,28 @@ library Base64 {
 
                 // Decode each byte in the chunk as a 6 bit block, and align them to form a block of 3 bytes
                 let a := sub(byte(28, input), 43)
+                // slither-disable-next-line incorrect-shift
                 if iszero(and(shl(a, 1), 0xffffffd0ffffffc47ff5)) {
                     mstore(0, errorSelector)
                     mstore(4, add(a, 49))
                     revert(0, 0x24)
                 }
                 let b := sub(byte(29, input), 43)
+                // slither-disable-next-line incorrect-shift
                 if iszero(and(shl(b, 1), 0xffffffd0ffffffc47ff5)) {
                     mstore(0, errorSelector)
                     mstore(4, add(b, 49))
                     revert(0, 0x24)
                 }
                 let c := sub(byte(30, input), 43)
+                // slither-disable-next-line incorrect-shift
                 if iszero(and(shl(c, 1), 0xffffffd0ffffffc47ff5)) {
                     mstore(0, errorSelector)
                     mstore(4, add(c, 49))
                     revert(0, 0x24)
                 }
                 let d := sub(byte(31, input), 43)
+                // slither-disable-next-line incorrect-shift
                 if iszero(and(shl(d, 1), 0xffffffd0ffffffc47ff5)) {
                     mstore(0, errorSelector)
                     mstore(4, add(d, 49))