Update AWS SDK, fixed GCC 9 on ubuntu 20.04

[fran6co]

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

Fixes #55

[dabonnie]

Hi @fran6co, thanks for the PR! You'll want to fix the build failures noted on the Travis builds.

[fran6co]

Not sure why the test is failing with a segmentation fault

[dabonnie]

FYI @emersonknapp @mm318.

I may be misremembering, but thought utils-common was stuck at 1.6 for Lex and Polly breaking changes. Thoughts on this PR?

[mm318]

I do remember there needed to be code changes to the Lex Cloud Extension when updating between some AWS SDK versions, and I think we've already done that once before. It may apply to this new AWS SDK version bump as well.

These particular Build & Test failures are unrelated to breaking changes to downstream dependencies though. However, bumping the AWS SDK version should involve some testing of downstream dependencies though.

[fran6co]

The main reason I did this PR is for porting the ROS packages to 20.04 and noetic. I only had to fix this other project -> aws-robotics/utils-ros1#36 for it to work

[fran6co]

Not sure why the test is failing with a segmentation fault

fixed segfault

[jikawa-az]

Following up on this, updated branch and retesting.

[jikawa-az]

@emersonknapp PTAL as well, this PR should add support for Focal which is not working for our images.