[improve][doc] relocate "Get Started" (pulsar-admin) to admin API and correct inaccurate descriptions

[Anonymitaet]

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What issue do you find in Pulsar docs?

1. Get Started of pulsar-admin is shown in Tutorials.

2. The wordings "Java admin API" in Admin API > Features > Functions and Admin API > Features > Schemas are inaccurate.

What is your suggestion?

1. Relocate it to Admin API - Get Started to improve the ease of use.

2. Correct it to "Java".

Any reference?

N/A

Are you willing to submit a PR?

• I'm willing to submit a PR!