static DocServiceFilter ofRegex(String regex) {
        requireNonNull(regex, "regex");
        return ofRegex(Pattern.compile(regex));
    }
Returns a {@link DocServiceFilter} which returns {@code true} when the concatenated name of the plugin,
service and method matches the specified {@code regex}.
The concatenated name will be {@code "pluginName + ':' + serviceName + '#' + methodName"}. For example:
<pre>{@code
grpc:com.example.grpc.FooService#EmptyCall // gRPC.
thrift:com.example.thrift.BarService#myMethod // Thrift.
annotated:com.example.annotated.BazService#myMethod // Annotated service.
}</pre>
core/src/main/java/com/linecorp/armeria/server/docs/DocServiceFilter.java