ci: regenerate fixtures upon changes to parser.h, alloc.h, array.h

This makes sense because the files are moved to `src/tree_sitter` upon
generation

.github/actions/cache/action.yml

@@ -18,6 +18,9 @@ runs:
           target/release/tree-sitter-*.wasm
         key: fixtures-${{ join(matrix.*, '_') }}-${{ hashFiles(
           'cli/generate/src/**',
+          'lib/src/parser.h',
+          'lib/src/array.h',
+          'lib/src/alloc.h',
           'xtask/src/*',
           'test/fixtures/grammars/*/**/src/*.c',
           '.github/actions/cache/action.yml') }}