MAINT: fix specs for CI matrix

.github/workflows/tests.yml

@@ -27,28 +27,28 @@ jobs:
       matrix:
         os: [ubuntu-latest]
         python-version: ["3.9", "3.10", "3.11", "3.12"]
-        sphinx: [">=5.0,<=7.*"]  # Newest Sphinx (any)
-        myst-parser: [">=1.0.0,<=2.*"]  # Newest MyST Parser (any)
+        sphinx: [">=5,<8"]  # Newest Sphinx (any)
+        myst-parser: [">=1,<3"]  # Newest MyST Parser (any)
         include:
           # Just check the other platforms once
           - os: windows-latest
             python-version: "3.10"
             sphinx: "~=7.0"
-            myst-parser: ">=2.0"
+            myst-parser: "~=2.0"
           - os: macos-latest
             python-version: "3.10"
             sphinx: "~=7.0"
-            myst-parser: ">=2.0"
+            myst-parser: "~=2.0"
           # Oldest known-compatible dependencies
           - os: ubuntu-latest
             python-version: "3.9"
-            sphinx: "~=5.0"
-            myst-parser: "~=1.0.0"
+            sphinx: "==5.0.0"
+            myst-parser: "==1.0.0"
           # Newest known-compatible dependencies
           - os: ubuntu-latest
             python-version: "3.12"
-            sphinx: "~=7.0"
-            myst-parser: "~=2.0.0"
+            sphinx: "==7.0.0"
+            myst-parser: "==2.0.0"
 
     runs-on: ${{ matrix.os }}
 
@@ -91,8 +91,10 @@ jobs:
       # for some reason the tests/conftest.py::check_nbs fixture breaks pytest-cov's cov-report outputting
       # this is why we run `coverage xml` afterwards (required by codecov)
 
+    # TEMPORARY FIX: Disable codecov until we can get it working again
     - name: Upload to Codecov
-      uses: codecov/codecov-action@v3
+      uses: codecov/[email protected]
+      if: false
       with:
         name: myst-nb-pytests
         flags: pytests