Hreflang iteration 2

Step 1: What is changing in this MR?

Fixing 3 common errors with hreflang:

1. Self-referencing hreflang not present - the hreflang implementation needs to specify both the preferred audience for the page itself, and its translated variants (only for localized solution pages)
2. Remove data-hid="i18n-alt-de-de" from the implementation. This must be formatted <link rel=”alternate” hreflang=”x” href=”https://example.com/alternate-page” /> with no additional code.
3. Include non-region hreflang alternatives to target language speakers in multiple locations for French and German.

• closes #3548 (closed)

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Step 2: Ensure that your changes comply with the following, where applicable:

• I, the Assignee, have run Axe tools on any updated pages, and fixed the relevant accessibility issues.
• These changes work on both Safari, Chrome, and Firefox.
• These changes have been reviewed for Visual Quality Assurance and Functional Quality Assurance on Mobile, Desktop, and Tablet.
• These changes work with our Google Analytics and SEO tools.
• These changes have been documented as expected.

Build Variables:

• Use Contentful Preview API