fi-0186: Unterminated Unicode escape sequence {:#fi-0186}

Unicode escape sequences in string literals must be terminated:

{% include “docs/reference/fidl/language/error-catalog/label/_bad.md” %}

{% includecode gerrit_repo="fuchsia/fuchsia" gerrit_path="tools/fidl/fidlc/tests/fidl/bad/fi-0186.test.fidl" exclude_regexp="\/\/ (Copyright 20|Use of|found in).*" %}

To terminate the escape sequence, add a closing brace }:

{% include “docs/reference/fidl/language/error-catalog/label/_good.md” %}

{% includecode gerrit_repo="fuchsia/fuchsia" gerrit_path="tools/fidl/fidlc/tests/fidl/good/fi-0186.test.fidl" exclude_regexp="\/\/ (Copyright 20|Use of|found in).*" %}