fix: fix maintenance branch regex

docs/usage/configuration.md

@@ -70,7 +70,7 @@ List of modules or file paths containing a [shareable configuration](shareable-c
 ### branches
 
 Type: `Array`, `String`, `Object`<br>
-Default: `['+([1-9])?(.{+([1-9]),x}).x', 'master', 'next', 'next-major', {name: 'beta', prerelease: true}, {name: 'alpha', prerelease: true}]`<br>
+Default: `['+([0-9])?(.{+([0-9]),x}).x', 'master', 'next', 'next-major', {name: 'beta', prerelease: true}, {name: 'alpha', prerelease: true}]`<br>
 CLI arguments: `--branches`
 
 The branches on which releases should happen. By default **semantic-release** will release:

docs/usage/workflow-configuration.md

@@ -34,7 +34,7 @@ It can be defined as a [glob](https://github.com/micromatch/micromatch#matching-
 
 If `name` doesn't match to any branch existing in the repository, the definition will be ignored. For example the default configuration includes the definition `next` and `next-major` which will become active only when the branches `next` and/or `next-major` are created in the repository. This allow to define your workflow once with all potential branches you might use and have the effective configuration evolving as you create new branches.
 
-For example the configuration `['+([1-9])?(.{+([1-9]),x}).x', 'master', 'next']` will be expanded as:
+For example the configuration `['+([0-9])?(.{+([0-9]),x}).x', 'master', 'next']` will be expanded as:
 ```js
 {
   branches: [