Make cargo-nextest more resilient (#715)

.config/nextest.toml

@@ -1,3 +1,14 @@
+# By default, retry a few times until pass the test within the specified timeout
+[profile.default]
+retries = 4
+slow-timeout = { period = "60s", terminate-after = 2 }
+
+# Run the following tests exclusively with longer timeout
 [[profile.default.overrides]]
-filter = 'test(/zenoh_session_unicast/)'
+filter = """
+test(=zenoh_session_unicast) |
+test(=zenoh_session_multicast) |
+test(=three_node_combination)
+"""
 threads-required = 'num-cpus'
+slow-timeout = { period = "60s", terminate-after = 6 }