docs:add FAQ.md abot how dfget connect to supernodes in mul-supernode mode

[yunfeiyanggzq]

Signed-off-by: yunfeiyangbuaa [email protected]

Ⅰ. Describe what this PR did

too many questions about this in dingding group

Ⅱ. Does this pull request fix one issue?

Ⅲ. Why don't you add test cases (unit test/integration test)? (你真的觉得不需要加测试吗？)

Ⅳ. Describe how to verify it

Ⅴ. Special notes for reviews

[starnop]

too many questions about this in dingding group

Good job. Could you please sort out a list of questions and open an issue to record that? THX.

[codecov-io]

Codecov Report

Merging #954 into master will increase coverage by 0.01%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master     #954      +/-   ##
==========================================
+ Coverage   46.42%   46.43%   +0.01%     
==========================================
  Files         116      116              
  Lines        6908     6908              
==========================================
+ Hits         3207     3208       +1     
  Misses       3443     3443              
+ Partials      258      257       -1

Impacted Files	Coverage Δ
supernode/daemon/mgr/scheduler/manager.go	22.6% <0%> (+0.68%)	⬆️

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[yunfeiyanggzq]

too many questions about this in dingding group

Good job. Could you please sort out a list of questions and open an issue to record that? THX.

ok

[yunfeiyanggzq]

@starnop please review it again

[starnop]

Good job. LGTM.

[starnop]

too many questions about this in dingding group

Good job. Could you please sort out a list of questions and open an issue to record that? THX.

@yunfeiyanggzq And please don't forget to open an issue to trace it. THX. 😄