Fix integration test (#12859)

.prettierignore

@@ -1,13 +1,29 @@
 .tmp
-dist/
 .cache/
 coverage/
+.nyc_output/
+.yarn/
+dist/
+node_modules/
+
 /tests/format/**/*.*
 !/tests/format/**/jsfmt.spec.js
 /tests/integration/cli/
-/tests/integration/plugins/
+/tests/integration/plugins/**/*.*
+!/tests/integration/plugins/automatic/node_modules/@prettier/plugin-foo/index.js
+!/tests/integration/plugins/automatic/node_modules/@user/prettier-plugin-foobar/index.js
+!/tests/integration/plugins/automatic/node_modules/prettier-plugin-bar/index.js
+!/tests/integration/plugins/automatic/package.json
+!/tests/integration/plugins/automatic/prettier-plugin-bar.js
+!/tests/integration/plugins/bespoke/node_modules/@company/prettier-plugin-bespoke/main.js
+!/tests/integration/plugins/defaultOptions/plugin.cjs
+!/tests/integration/plugins/extensions/plugin.cjs
+!/tests/integration/plugins/flushLineSuffix/plugin.cjs
+!/tests/integration/plugins/options-string/plugin.cjs
+!/tests/integration/plugins/options/plugin.cjs
+!/tests/integration/plugins/preprocess/plugin.cjs
 /tests/integration/custom-parsers/
+
 /website/build/
 /website/static/lib/
 /website/static/playground.js
-.nyc_output