Broken Links in RPC Service and Authentication

[theresalech]

There are a few broken links in the Protocol Spec which should be fixed.

Current: In 5.2 RPC Service section, there are two instances where "RPC Specification" links to https://github.com/smartdevicelink/sdl_core/blob/master/src/components/interfaces/MOBILE_API.xml, which gives a 404.

Expected: In 5.2 RPC Service section, both instances of "RPC Specification" should link to https://github.com/smartdevicelink/rpc_spec/blob/master/MOBILE_API.xml.

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Current: In 7.1 Authentication section, "SSL Security Level" links to https://www.openssl.org/docs/man1.1.0/man3/SSL_CTX_get_security_level.html, which gives a "Page Not Found" error.

Expected: In 7.1 Authentication section, "SSL Security Level" should link to https://www.openssl.org/docs/man1.1.1/man3/SSL_CTX_get_security_level.html.

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Current: In 7.1 Authentication section, "SDL Overview Guides" links to https://smartdevicelink.com/en/guides/pull_request/sdl-overview-guides/security/protected-services/, which gives a 404.

Expected: In 7.1 Authentication section, "SDL Overview Guides" should link to https://smartdevicelink.com/en/guides/sdl-overview-guides/security/protected-services/.