config: ignore math during spell check

.vscode/settings.json

@@ -7,10 +7,13 @@
     "spellright.language": [
         "en_US"
     ],
+    "spellright.ignoreRegExps": [
+        "/.. math::[^]*?.. endmath/gm",
+    ],
     "spellright.documentTypes": [
         "markdown",
         "latex",
         "plaintext",
         "python"
     ]
-}
+}

doc/api/signaltypes.rst

@@ -246,3 +246,5 @@ Fahrenheit (°F) or Kelvin (K), you can use the following conversion formulas:
       °\!F & = & °\!C \cdot \frac{9}{5} + 32\\
       K & = & °\!C + 273.15
    \end{eqnarray}
+
+.. endmath