fix(header): reset subnav state on page change + position fixed

[nathanjamal]

reset subnav state on page change. Plus added a hook into the burger menu toggle event so parent app can do things like lock the page scroll when nav is open. Also changed back to position fixed for more stable sticky behaviour

BREAKING CHANGE: Header changed from position sticky to position fixed

HEYUI-365

Pull Request

Description

Describe your changes (or add ticket description) and add relevant screenshots

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Documentation change

How do I test this

• Add steps to test
• in bullet point format
• preferably you can add link to the storybook build in the PR

Checklist

Did you remember to take care of the following?

• npm i – for new NPM dependencies.
• npm run lint - to check for linting issues
• npm run test - to run unit tests
• npm run test:sh:docker - to run screenshot tests, detail instruction

New Feature / Bug Fix

• Run unit tests to ensure all existing tests are still passing.
• Add new passing unit tests to cover the code introduced by your pr.

Thanks for contributing!

[github-actions]

Pull Request Test Coverage Report for Build 5246051666

• 9 of 9 (100.0%) changed or added relevant lines in 2 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.3%) to 92.485%

---

Totals
Change from base Build 5212697865:	0.3%
Covered Lines:	1675
Relevant Lines:	1737

---

💛 - Coveralls

[github-actions]

Coverage report

St.❔	Category	Percentage	Covered / Total
🟢	Statements	96.2%	1874/1948
🟢	Branches	81.86%	528/645
🟢	Functions	83.67% (+1.2% 🔼)	164/196
🟢	Lines	96.43%	1675/1737

Test suite run success

402 tests passing in 56 suites.

Report generated by 🧪jest coverage report action from ae6daa4

[github-actions]

Compiled a new version demo.

[supcar]

🎉 This PR is included in version 9.0.0 🎉

The release is available on:

• npm package (@latest dist-tag)
• GitHub release

Your semantic-release bot 📦🚀

[coveralls]

Pull Request Test Coverage Report for Build 5246051666

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

• For more information on this, see Tracking coverage changes with pull request builds.
• To avoid this issue with future PRs, see these Recommended CI Configurations.
• For a quick fix, rebase this PR at GitHub. Your next report should be accurate.

Details

• 9 of 9 (100.0%) changed or added relevant lines in 2 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.3%) to 92.485%

---

Totals
Change from base Build 5212697865:	0.3%
Covered Lines:	1675
Relevant Lines:	1737

---

💛 - Coveralls