Use fieldparams for BLS public key (#10042)

* Use fieldparams for pubkey length

* Fix validator tests

* fix more tests

* fix mock validator

* Fix typo

* bunch of typos

* Update bytes.go

* Update BUILD.bazel

Co-authored-by: prylabs-bulldozer[bot] <58059840+prylabs-bulldozer[bot]@users.noreply.github.com>

crypto/bls/common/BUILD.bazel

@@ -12,4 +12,5 @@ go_library(
         "//crypto/bls:__subpackages__",
         "//testing:__subpackages__",
     ],
+    deps = ["//config/fieldparams:go_default_library"],
 )

crypto/bls/common/constants.go

@@ -1,10 +1,12 @@
 package common
 
+import fieldparams "github.com/prysmaticlabs/prysm/config/fieldparams"
+
 // ZeroSecretKey represents a zero secret key.
 var ZeroSecretKey = [32]byte{}
 
 // InfinitePublicKey represents an infinite public key (G1 Point at Infinity).
-var InfinitePublicKey = [48]byte{0xC0}
+var InfinitePublicKey = [fieldparams.BLSPubkeyLength]byte{0xC0}
 
 // InfiniteSignature represents an infinite signature (G2 Point at Infinity).
 var InfiniteSignature = [96]byte{0xC0}