Don't bother trying sysmon tracer

.. its speed advantages don't help branch coverage, just line coverage.

.github/workflows/test.yml

@@ -41,19 +41,13 @@ jobs:
         - '3.13.0-alpha.0 - 3.13'
         os-version:
         - 'ubuntu-latest'
-        coverage-core:
-        - 'ctrace'
         include:
           - os-version: 'macos-latest'
             python-version: '3.x'
           - os-version: 'windows-latest'
             python-version: '3.x'
-          - os-version: 'ubuntu-latest'
-            python-version: '3.12'
-            coverage-core: 'sysmon'
           - os-version: 'ubuntu-latest'
             python-version: 'pypy-3.10'
-            coverage-core: 'pytrace'
 
     runs-on: ${{ matrix.os-version }}
     steps:
@@ -74,13 +68,13 @@ jobs:
       run: make mypy PYTHON=python
 
     - name: Test
-      run: make coverage PYTHON=python COVERAGE_CORE=${{ matrix.coverage-core }}
+      run: make coverage PYTHON=python
 
     - name: Upload Coverage as artifact
       if: always()
       uses: actions/upload-artifact@v4
       with:
-        name: coverage for ${{ matrix.python-version }} on ${{ matrix.os-version }} ${{ matrix.coverage-core }}
+        name: coverage for ${{ matrix.python-version }} on ${{ matrix.os-version }}
         path: coverage.xml
 
   pre-commit:

Makefile

@@ -55,9 +55,6 @@ BUILDDIR      = _build
 html:
 	@$(SPHINXBUILD) -M $@ "$(SOURCEDIR)" "$(BUILDDIR)" $(SPHINXOPTS) $(O)
 
-# Pass the desired coverage tracer name to subprocesses
-export COVERAGE_CORE
-
 # Copyright (C) 2021 Jeff Epler <jepler@gmail.com>
 # SPDX-FileCopyrightText: 2021 Jeff Epler
 #