Use of `#` in commit body causes `closes` false positive

Notes:

• This was first opened as an issue against semantic-release.
• This may be a duplicate of #391.

Current behavior

Had this happen a few times now but manually fixed previously. If a hash # appears in the commit body, it is seen as a closes in the release notes and changelog. An existing example follows.

Commit https://github.com/saltstack-formulas/template-formula/commit/3a072c7:

ci(travis): prevent `release` stage running for PRs

* The `release` stage will always fail due to security reasons:
  - E.g. https://travis-ci.com/saltstack-formulas/template-formula/jobs/180068519#L466.
  - Discussed: #42 (comment).
* The `release` stage is unnecessary for PRs until the merge to `master`, in any case.

Resulted in both:

• https://github.com/saltstack-formulas/template-formula/releases/tag/v0.7.2
• https://github.com/saltstack-formulas/template-formula/blob/master/CHANGELOG.md#072-2019-02-24

Specifically:

• travis: prevent release stage running for PRs (3a072c7), closes /travis-ci.com/saltstack-formulas/template-formula/jobs/180068519#L466 /github.com/saltstack-formulas/template-formula/pull/42#issuecomment-466446324

Expected behavior

The closes shouldn't have been present:

• travis: prevent release stage running for PRs (3a072c7)

Environment

• semantic-release version: 15
• CI environment: Travis CI
• Plugins used: changelog@3, exec@3 & git@7
• semantic-release configuration: release.config.js
• CI logs: Check under the Release stage

Further example that was manually fixed

• Commit: https://github.com/saltstack-formulas/template-formula/commit/068a94d
• Manual fix: https://github.com/saltstack-formulas/template-formula/commit/be4571d