[server] Use 'new Probot({ logLevel })' instead of the deprecated 'LOG_LEVEL' environment variable

[jankeromnes]

Fixes #3181

[jankeromnes]

Seems to successfully get rid of the warning:

Before

$ kubectl logs server-59d6c4d9bb-68bv4 | grep LOG_LEVEL
WARN     (Deprecation): [probot] "LOG_LEVEL" environment variable is deprecated. Use "new Probot({ logLevel })" instead
    Deprecation: [probot] "LOG_LEVEL" environment variable is deprecated. Use "new Probot({ logLevel })" instead
$ 

After

$ kubectl logs server-756d7fcf8b-kwq4w | grep LOG_LEVEL
$ 

[jankeromnes]

Side-note: Some other warnings are still there though:

Before

$ kubectl logs server-59d6c4d9bb-68bv4 | grep probot | less

WARN     (Deprecation): [probot] "LOG_LEVEL" environment variable is deprecated. Use "new Probot({ logLevel })" instead
    Deprecation: [probot] "LOG_LEVEL" environment variable is deprecated. Use "new Probot({ logLevel })" instead
        at new Probot (/app/node_modules/probot/lib/probot.js:44:27)
WARN     (Deprecation): [probot] "app.route()" is deprecated, use the "getRouter()" argument from the app function instead: "({ app, getRouter }) => { ... }"
    Deprecation: [probot] "app.route()" is deprecated, use the "getRouter()" argument from the app function instead: "({ app, getRouter }) => { ... }"
        at GithubApp.route (/app/node_modules/probot/lib/probot.js:224:23)
        at Object.load (/app/node_modules/probot/lib/load.js:36:9)
        at GithubApp.load (/app/node_modules/probot/lib/probot.js:154:16)
TRACE    (probot): secretOrPrivateKey must have a value
WARN     (probot): Probot is unable to retrieve app information from GitHub for event subscription verification.
  - https://github.com/probot/probot/issues

After

kubectl logs server-756d7fcf8b-kwq4w | grep probot | less

WARN     (Deprecation): [probot] "app.route()" is deprecated, use the "getRouter()" argument from the app function instead: "({ app, getRouter }) => { ... }"
    Deprecation: [probot] "app.route()" is deprecated, use the "getRouter()" argument from the app function instead: "({ app, getRouter }) => { ... }"
        at GithubApp.route (/app/node_modules/probot/lib/probot.js:224:23)
        at Object.load (/app/node_modules/probot/lib/load.js:36:9)
        at GithubApp.load (/app/node_modules/probot/lib/probot.js:154:16)
[...]
TRACE    (probot): secretOrPrivateKey must have a value
WARN     (probot): Probot is unable to retrieve app information from GitHub for event subscription verification.
  - https://github.com/probot/probot/issues

Diff

The LOG_LEVEL warning is fixed, but the app.route() warning is still there -- should this one also get fixed?

(The other warnings seems to indicate that my dev staging deployment has no GitHub App configured, but maybe that's expected in dev staging?)

[csweichel]

LGTM