router_check_tool: fix ASSERT in path_rewrite test

[jyotima]

Signed-off-by: Jyoti Mahapatra jmahapatra@lyft.com

Description: When multiple test validations are mentioned in the validation section,
eg:

"validate": {
        "host_rewrite": "api.lyft.com",
        "virtual_host_name": "api",
        "path_rewrite": "/pre/test",
        "cluster_name": "www2"
      }

finalizeRequestHeaders is called multiple times causing ASSERT failures. None of the existing tests covered this scenario. Now few tests have been added to simulate the error.

Before the fix the failure looked like this

[2019-05-29 19:47:48.210][1405009][critical][assert] [source/common/router/config_impl.cc:557] assert failure: case_sensitive_ ? absl::StartsWith(path, matched_path) : absl::StartsWithIgnoreCase(path, matched_path).

Risk Level: Low
Testing:

• Added breaking tests and fixed them using the fix.
• Tested the tool against lyft's routes

[jmarantz]

Is there a test that should be added that would fail without your new production code? Or is that implicit in the new json & yaml you added?
[edit]
never mind you covered this in the description. Thanks. LGTM modulo nit.

[jyotimahapatra]

#730