feat(navigation): add screen reader text to hamburger button

[mryunt02]

describe your changes... Added screen reader text to the navigation hamburger button to improve accessibility.

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[linux-foundation-easycla[bot]]

• :white_check_mark:login: mryunt02 / (595b87200c9e0510ad862e40b64a28c384b9f71f)

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[snitin315]

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