Update EIP-225: Update eip-225.md to fix typo "singer" (ethereum#8038)

Update eip-225.md

Fix typo "singer".

EIPS/eip-225.md

@@ -146,7 +146,7 @@ To authorize a block for the network, the signer needs to sign the block's sigha
 
 The sighash is signed using the standard `secp256k1` curve, and the resulting 65 byte signature (`R`, `S`, `V`, where `V` is `0` or `1`) is embedded into the `extraData` as the trailing 65 byte suffix.
 
-To ensure malicious signers (loss of signing key) cannot wreck havoc in the network, each singer is allowed to sign **maximum one** out of **`SIGNER_LIMIT`** consecutive blocks. The order is not fixed, but in-turn signing weighs more (**`DIFF_INTURN`**) than out of turn one (**`DIFF_NOTURN`**).
+To ensure malicious signers (loss of signing key) cannot wreck havoc in the network, each signer is allowed to sign **maximum one** out of **`SIGNER_LIMIT`** consecutive blocks. The order is not fixed, but in-turn signing weighs more (**`DIFF_INTURN`**) than out of turn one (**`DIFF_NOTURN`**).
 
 #### Authorization strategies