docs: use a backslash to escape the pipe in regex within a markdown table

README.md

@@ -92,7 +92,7 @@ As specified in the previous chapter, these variables are only used to generated
 | `changelog-title` / `SEMREL_CHANGELOG_TITLE`           | [changelogTitle @semantic-release/changelog option](https://github.com/semantic-release/changelog#options). You might want to use markdown format (for example `# MyApp Changelog`).                                                | _none_                                                                                                                                |
 | `dry-run` / `SEMREL_DRY_RUN`                           | Activate the [dryRun semantic-release option](https://github.com/semantic-release/semantic-release/blob/master/docs/usage/configuration.md#dryrun) if present.                                                                      | _none_                                                                                                                                |
 | `auto-release-enabled` / `SEMREL_AUTO_RELEASE_ENABLED` | When set to `true` the job start automatically. When not set (default), the job is manual.                                                                                                                                          | _none_                                                                                                                                |
-| `branches-ref` / `SEMREL_BRANCHES_REF`                 | Regular expression pattern matching branches from which releases should happen (should match your [semantic-release configuration](https://semantic-release.gitbook.io/semantic-release/usage/configuration#branches))              | `/^(master|main)$/` |
+| `branches-ref` / `SEMREL_BRANCHES_REF`                 | Regular expression pattern matching branches from which releases should happen (should match your [semantic-release configuration](https://semantic-release.gitbook.io/semantic-release/usage/configuration#branches))              | `/^(master\|main)$/` |
 | `tag-format` / `SEMREL_TAG_FORMAT`                     | [tagFormat semantic-release option](https://github.com/semantic-release/semantic-release/blob/master/docs/usage/configuration.md#tagformat). :warning: don't forget to double the `$` character so it is not interpreted by GitLab. | `$${version}`                                                                                                                         |
 | `hooks-dir` / `SEMREL_HOOKS_DIR`                       | [Hook scripts](#hook_scripts) folder.                                                                                                                                                                                               | `.`                                                                                                                                   |
 | `commit-message` / `SEMREL_COMMIT_MESSAGE`             | Add a custom commit message based on [semantic-release/git option](https://github.com/semantic-release/git#message).                                                                                                                | _none_ (uses semantic-release default commit message)                                                                                 |