Skip some tests on riscv

tests/core/net/test_core_net.odin

@@ -608,6 +608,11 @@ test_udp_echo :: proc(t: ^testing.T) {
 test_dns_resolve :: proc(t: ^testing.T) {
 	// NOTE: This test depends on external factors, so if it fails, an IP
 	// address may have changed or become unavailable.
+	// It regularly fails on the RISC-V CI runners, so we skip it there
+	when ODIN_ARCH == .riscv64 {
+		log.infof("Skipped on riscv64")
+		return
+	}
 
 	// The net API returns only one address per protocol version, and DNS
 	// records can store many, so we'll have to check all possibilities.

tests/core/sync/test_core_sync.odin

@@ -538,6 +538,14 @@ test_ticket_mutex :: proc(t: ^testing.T) {
 
 @test
 test_benaphore :: proc(t: ^testing.T) {
+	// NOTE(Jeroen): Regularly times out on the simulated RISC-V CI runners,
+	//               so we're skipping the test there.
+
+	when ODIN_ARCH == .riscv64 {
+		log.infof("Skipped on riscv64")
+		return
+	}
+
 	testing.set_fail_timeout(t, FAIL_TIME)
 
 	Data :: struct {