fix(nav-bar): null check tabs when finding tab

[tomaszgrabowski]

PR Checklist

Please check that your PR fulfills the following requirements:

• The commit message follows our guidelines
• Tests for the changes have been added or this is not a bug fix / enhancement
• Docs have been added, updated, or were not required

PR Type

What kind of change does this PR introduce?

[x] Bugfix
[ ] Enhancement
[ ] Documentation content changes
[ ] Code style update (formatting, local variables)
[ ] Refactoring (no functional changes, no api changes)
[ ] Build related changes
[ ] CI related changes
[ ] Infrastructure changes
[ ] Other... Please describe:

What is the current behavior?

Currently on browser window resize there is a possibility that tabs will not be found on time. This will be ended wit console error Cannot read property 'length' of null

Issue Number:

What is the new behavior?

No error

Does this PR introduce a breaking change?

[ ] Yes
[x] No

Other information

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[Splaktar]

Thank you for this issue report and contribution!

Can you please update the JSDoc and sign the CLA?

[tomaszgrabowski]

@googlebot I signed it!

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[tomaszgrabowski]

Thank you for this issue report and contribution!

Can you please update the JSDoc and sign the CLA?

@Splaktar required changes uploaded. Thanks for the review.

[Splaktar]

LGTM

[Splaktar]

CI is broken due to NPM being down atm.