Increment number of backends to account for HPX

Author: Alexander Strack

tests/backend_types.cpp

@@ -44,7 +44,7 @@ TEST(BackendType, to_string) {
 
 TEST(BackendType, to_string_unknown) {
     // check conversions to std::string from unknown backend_type
-    EXPECT_CONVERSION_TO_STRING(static_cast<plssvm::backend_type>(7), "unknown");
+    EXPECT_CONVERSION_TO_STRING(static_cast<plssvm::backend_type>(8), "unknown");
 }
 
 // check whether the std::string -> plssvm::backend_type conversions are correct

tests/csvm_factory.cpp

@@ -234,7 +234,7 @@ TEST(CSVMFactory, factory_named_parameter) {
 }
 
 TEST(CSVMFactory, invalid_backend) {
-    EXPECT_THROW_WHAT(std::ignore = plssvm::make_csvm(static_cast<plssvm::backend_type>(7)),
+    EXPECT_THROW_WHAT(std::ignore = plssvm::make_csvm(static_cast<plssvm::backend_type>(8)),
                       plssvm::unsupported_backend_exception,
                       "Unrecognized backend provided!");
 }