Modify some integration tests to allow them to pass on more limited systems

[bcsgh]

Several integration tests require that port 8080 be available. As this is one of the more common alternative HTTP ports, it is likely to be unavailable. A bit of pre-processor hacking allows the build to select a different port if needed.

Another issue is that tests that use httpserver::file_response require that the expected path be an actual file. Some build environments (the provoking case is where I need to use libhttpserver from a Bazel build, which uses a sandbox built from symlinks, and I need to also build and run the test under bazel to ensure that build is also correct)

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NOTE: I don't know how to make Codacy/cppcheck happy with the new config HTTPSERVER_PORT (it seems to already be fine with the other config: HTTPSERVER_NO_LOCAL_FS) . The most useful thing I've found is this but I don't know where to go from there.

Help or suggestions would be appreciated.

[etr]

NOTE: I don't know how to make Codacy/cppcheck happy with the new config HTTPSERVER_PORT (it seems to already be fine with the other config: HTTPSERVER_NO_LOCAL_FS) . The most useful thing I've found is this but I don't know where to go from there.

I disabled the check for the test files, but codacy even on re-runs keeps complaining about the issue. I suspect that it keeps the settings it had at the time the PR was created when evaluating a PR. I'll manually check codacy before merging this change to see if there are other issues, but in regard to the definition of the port parameter, don't worry about it.

[bcsgh]

Looks like codacy caches config per commit rather than per PR, adding a new commit seems to make it start over. :-)

[etr]

Looks good. Merged it in.