ignore direnv configs (#8861)

https://direnv.net/ is a useful tool but its configs are developer-specific

.gitignore

@@ -52,4 +52,8 @@ onnxruntime/python/version_info.py
 /tools/perf_util/target/classes
 /tools/perf_util/src/main/resources
 /orttraining/orttraining/eager/ort_aten.g.cpp
-/orttraining/orttraining/eager/ort_customops.g.cpp
+/orttraining/orttraining/eager/ort_customops.g.cpp
+
+# direnv, posh-direnv
+.envrc
+.psenvrc