textlitn-scripts: Prevent duplicated register

[azu]

From textlint/textlint-scripts#38

--require textlint-scripts/register-ts
--require textlint-scripts/register-ts

throw error TS7006: Parameter 'obj' implicitly has an 'any' type.

We need to detect .mocharc file and prevent duplicated register.

[azu]

https://mochajs.org/#-config-path
--no-config will helps it.

[azu]

However, if pass --no-config by default, the user can not setting other config via .mocharc.*.
for example, timeout options should be configurable.