add APP_ID env.

[JaredTan95]

No description provided.

[codecov-io]

Codecov Report

Merging #2067 into master will increase coverage by <.01%.
The diff coverage is 20%.

@@             Coverage Diff              @@
##             master    #2067      +/-   ##
============================================
+ Coverage     49.96%   49.97%   +<.01%     
- Complexity     1978     1979       +1     
============================================
  Files           401      401              
  Lines         12406    12411       +5     
  Branches       1278     1279       +1     
============================================
+ Hits           6199     6202       +3     
- Misses         5748     5750       +2     
  Partials        459      459

Impacted Files	Coverage Δ	Complexity Δ
...internals/provider/DefaultApplicationProvider.java	65.95% <20%> (-5.48%)	11 <0> (ø)
.../apollo/internals/RemoteConfigLongPollService.java	80.36% <0%> (+1.22%)	28% <0%> (+1%)	⬆️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 553d781...b4b7795. Read the comment docs.

[coveralls]

Coverage increased (+0.003%) to 53.67% when pulling b4b7795 on JaredTan95:apollo-id-env into 553d781 on ctripcorp:master.

[nobodyiam]

LGTM