fix: remove case sensitive checking of probe headers

pkg/probe/http/request.go

@@ -113,7 +113,7 @@ func formatURL(scheme string, host string, port int, path string) *url.URL {
 func v1HeaderToHTTPHeader(headerList []v1.HTTPHeader) http.Header {
 	headers := make(http.Header)
 	for _, header := range headerList {
-		headers[header.Name] = append(headers[header.Name], header.Value)
+		headers.Add(header.Name, header.Value)
 	}
 	return headers
 }

pkg/probe/http/request_test.go

@@ -78,3 +78,49 @@ func Test_v1HeaderToHTTPHeader(t *testing.T) {
 		})
 	}
 }
+
+func TestHeaderConversion(t *testing.T) {
+	testCases := []struct {
+		headers  []v1.HTTPHeader
+		expected http.Header
+	}{
+		{
+			[]v1.HTTPHeader{
+				{
+					Name:  "Accept",
+					Value: "application/json",
+				},
+			},
+			http.Header{
+				"Accept": []string{"application/json"},
+			},
+		},
+		{
+			[]v1.HTTPHeader{
+				{Name: "accept", Value: "application/json"},
+			},
+			http.Header{
+				"Accept": []string{"application/json"},
+			},
+		},
+		{
+			[]v1.HTTPHeader{
+				{Name: "accept", Value: "application/json"},
+				{Name: "Accept", Value: "*/*"},
+				{Name: "pragma", Value: "no-cache"},
+				{Name: "X-forwarded-for", Value: "username"},
+			},
+			http.Header{
+				"Accept":          []string{"application/json", "*/*"},
+				"Pragma":          []string{"no-cache"},
+				"X-Forwarded-For": []string{"username"},
+			},
+		},
+	}
+	for _, test := range testCases {
+		headers := v1HeaderToHTTPHeader(test.headers)
+		if !reflect.DeepEqual(headers, test.expected) {
+			t.Errorf("Expected %v, got %v", test.expected, headers)
+		}
+	}
+}