Fixed CI tests by overriding value MBEDTLS_ENTROPY_MAX_SOURCES

Override define MBEDTLS_ENTROPY_MAX_SOURCES from 1 to 3 in baremetal_test.h

mbedtls_entropy_init adds 2 sources already so max must be 3 so that
one source can be added with mbedtls_entropy_add_source.
diff --git a/configs/baremetal_test.h b/configs/baremetal_test.h
index b107bd7..33b5167 100644
--- a/configs/baremetal_test.h
+++ b/configs/baremetal_test.h
@@ -45,4 +45,7 @@
 
 #undef MBEDTLS_NO_PLATFORM_ENTROPY
 
+#undef  MBEDTLS_ENTROPY_MAX_SOURCES
+#define MBEDTLS_ENTROPY_MAX_SOURCES 3
+
 #endif /* MBEDTLS_BAREMETAL_USER_CONFIG_H */