Fix Dead links in testrtc description - Issue #247

[rantonysamy]

Description
Removed "Other test pages section" from README.md file

Purpose
Fix Dead links in testrtc description - that takes users to 404.

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[rantonysamy]

I signed it!

[googlebot]

CLAs look good, thanks!

[KaptenJansson]

LGTM (test failure is unrelated to this)