tiup leaks credential through environment printing

[mzhang77]

Bug Report

1. What did you do?
   any tiup cluster command, e.g.

tiup cluster list

2. What did you expect to see?
   The command should be safe to run

3. What did you see instead?
   In ~/.tiup/logs/tiup-cluster-debug-2023-12-09-23-45-09.log
   and ~/.tiup/storage/cluster/audit/XXXX AWS secrets leaks through ENV var printing

 ... "AWS_SECRET_ACCESS_KEY=REDACTED", ...

Same information also leak into

5. What version of TiUP are you using (tiup --version)?

tiup --version
1.16.0 tiup
Go Version: go1.21.11
Git Ref: v1.16.0
GitHash: e543145831d44a863366ff8c379d25980730bbd1

[mzhang77]

I think code is here:

tiup/components/cluster/command/root.go

Line 278 in c1a14a5

zap.L().Debug("Environment variables", zap.Strings("env", os.Environ()))

and

tiup/components/dm/command/root.go

Line 235 in c1a14a5

zap.L().Debug("Environment variables", zap.Strings("env", os.Environ()))

There is no where in tiup that user can set log level. By default this debug information should not write to file.