privval: add ctx to privval interface (#6240)

## Description

- Add `context.Context` to Privval interface

This pr does not introduce context into our custom privval connection protocol because this will be removed in the next release. When this pr is released.

state/state_test.go

@@ -2,6 +2,7 @@ package state_test
 
 import (
 	"bytes"
+	"context"
 	"fmt"
 	"math"
 	"math/big"
@@ -363,7 +364,7 @@ func TestProposerFrequency(t *testing.T) {
 			votePower := int64(tmrand.Int()%maxPower) + 1
 			totalVotePower += votePower
 			privVal := types.NewMockPV()
-			pubKey, err := privVal.GetPubKey()
+			pubKey, err := privVal.GetPubKey(context.Background())
 			require.NoError(t, err)
 			val := types.NewValidator(pubKey, votePower)
 			val.ProposerPriority = tmrand.Int64()

state/validation_test.go

@@ -1,6 +1,7 @@
 package state_test
 
 import (
+	"context"
 	"testing"
 	"time"
 
@@ -199,7 +200,7 @@ func TestValidateBlockCommit(t *testing.T) {
 		)
 		require.NoError(t, err, "height %d", height)
 
-		bpvPubKey, err := badPrivVal.GetPubKey()
+		bpvPubKey, err := badPrivVal.GetPubKey(context.Background())
 		require.NoError(t, err)
 
 		badVote := &types.Vote{
@@ -215,9 +216,9 @@ func TestValidateBlockCommit(t *testing.T) {
 		g := goodVote.ToProto()
 		b := badVote.ToProto()
 
-		err = badPrivVal.SignVote(chainID, g)
+		err = badPrivVal.SignVote(context.Background(), chainID, g)
 		require.NoError(t, err, "height %d", height)
-		err = badPrivVal.SignVote(chainID, b)
+		err = badPrivVal.SignVote(context.Background(), chainID, b)
 		require.NoError(t, err, "height %d", height)
 
 		goodVote.Signature, badVote.Signature = g.Signature, b.Signature