Fix 387: TravisCI is failing

[odanado]

ref: #387

[odanado]

Occurred an error.

(node:6761) UnhandledPromiseRejectionWarning: /home/travis/build/GoogleChrome/rendertron/middleware/node_modules/ava/lib/serialize-error.js:39
		} catch {}
		        ^
SyntaxError: Unexpected token {
    at createScript (vm.js:80:10)
    at Object.runInThisContext (vm.js:139:10)
    at Module._compile (module.js:617:28)
    at Object.Module._extensions..js (module.js:664:10)
    at Module.load (module.js:566:32)
    at tryModuleLoad (module.js:506:12)
    at Function.Module._load (module.js:498:3)
    at Module.require (module.js:597:17)
    at require (internal/module.js:11:18)
    at Object.<anonymous> (/home/travis/build/GoogleChrome/rendertron/middleware/node_modules/ava/lib/api.js:18:24)
(node:6761) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). (rejection id: 1)
(node:6761) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.

[odanado]

ava 3.0.0 no longer supports nodejs v8. Therefore, the above error has occurred.

https://github.com/avajs/ava/releases/tag/v3.0.0

Supported Node.js versions
We now support Node.js 10, 12 and 13. The minimal versions are 10.18.0, 12.14.0 and 13.5.0 respectively.

[odanado]

Do you want to update the nodejs version of Travis CI from 8 to 12?

[AVGP]

Yeah, let's do that. The relevant line is in package.json, please include this in the PR :)

[odanado]

datastore-cache-test › refreshCache refreshes cache is failing in nodejs 10 🤔
https://travis-ci.org/github/GoogleChrome/rendertron/jobs/683940122

I will try to find out the cause of the error.

[git-ekuo]

@odanado , @AVGP

This issue https://travis-ci.org/github/GoogleChrome/rendertron/jobs/683940122 that you are experiencing shall be addressed by #381. I already have a PR (#389) open for it, and it's failing with the issue you are trying to fix. I'd suggest that we let this one go first without fixing the refreshCache test error.

What do you think?

[AVGP]

Thanks @odanado for this! Next up is looking into the failing cache test. That one used to be flaky and it's being looked into in #381 :)