Merging to release-5.2.2: TT-10344 Fix rpc ClientIsConnected (#5692)

TT-10344 Fix rpc ClientIsConnected (#5692)

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## Description
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Reverting changes introduced in `func (r rpcOpts) ClientIsConnected()
bool` onhttps://github.com//pull/5574.

`clientIsConnected` fn is called on `FuncClientSingleton`
https://github.com/TykTechnologies/tyk/blob/master/rpc/rpc_client.go#L469
and if it fails while trying to `GroupLogin`, the function `recoverOps`
will not ever be able to recover
https://github.com/TykTechnologies/tyk/blob/master/rpc/rpc_client.go#L444
and exit emergency mode.




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rpc/rpc_client.go

@@ -72,7 +72,7 @@ type rpcOpts struct {
 
 func (r rpcOpts) ClientIsConnected() bool {
 	if v := r.clientIsConnected.Load(); v != nil {
-		return v.(bool) && !r.GetEmergencyMode()
+		return v.(bool)
 	}
 
 	return false

rpc/rpc_client_test.go

@@ -44,45 +44,28 @@ func TestClientIsConnected(t *testing.T) {
 	t.Parallel()
 
 	testCases := []struct {
-		name          string
-		connected     bool
-		emergencyMode bool
-		expected      bool
+		name      string
+		connected bool
+		expected  bool
 	}{
 		{
-			name:          "When client is connected and not in emergency mode",
-			connected:     true,
-			emergencyMode: false,
-			expected:      true,
+			name:      "When client is connected and not in emergency mode",
+			connected: true,
+			expected:  true,
 		},
 		{
-			name:          "When client is disconnected and not in emergency mode",
-			connected:     false,
-			emergencyMode: false,
-			expected:      false,
-		},
-		{
-			name:          "When client is connected and in emergency mode",
-			connected:     true,
-			emergencyMode: true,
-			expected:      false,
-		},
-		{
-			name:          "When client is disconnected and in emergency mode",
-			connected:     false,
-			emergencyMode: true,
-			expected:      false,
+			name:      "When client is disconnected and not in emergency mode",
+			connected: false,
+			expected:  false,
 		},
 	}
 
 	for _, tt := range testCases {
 		t.Run(tt.name, func(t *testing.T) {
 			r := rpcOpts{}
 			r.clientIsConnected.Store(tt.connected)
-			r.emergencyMode.Store(tt.emergencyMode)
 			defer func() {
 				r.clientIsConnected.Store(false)
-				r.emergencyMode.Store(false)
 			}()
 
 			got := r.ClientIsConnected()