Have cli analysis tests explicitly set multithreading env variables t…

…o 1.

This commit adds an auto-used fixture for all analysis tests, that sets the environment variables for multithreading `OMP_NUM_THREADS`, `MKL_NUM_THREADS`, and `NUMEXPR_NUM_THREADS` all to 1. This can cause the issue of those tests hanging, as numpy uses all resources available if those env variables are not explicitly set.

tests/ert/ui_tests/cli/conftest.py

@@ -0,0 +1,16 @@
+import os
+
+import pytest
+
+
+@pytest.fixture(autouse=True)
+def reduce_omp_num_threads_count():
+    old_omp_num_threads = os.environ.get("OMP_NUM_THREADS")
+    os.environ["OMP_NUM_THREADS"] = "1"
+
+    yield
+
+    if old_omp_num_threads is None:
+        del os.environ["OMP_NUM_THREADS"]
+    else:
+        os.environ["OMP_NUM_THREADS"] = old_omp_num_threads