Add Unit Test for All Notification Package

[haoel]

1. Add Unit Test for all notification package
2. make the generic Yaml/JSON marshal/unmarshal for all enum type

[codecov-commenter]

Codecov Report

Base: 99.51% // Head: 99.71% // Increases project coverage by +0.20% 🎉

Coverage data is based on head (8aa878d) compared to base (fb8ad1a).
Patch coverage: 100.00% of modified lines in pull request are covered.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #200      +/-   ##
==========================================
+ Coverage   99.51%   99.71%   +0.20%     
==========================================
  Files          49       70      +21     
  Lines        4088     4975     +887     
==========================================
+ Hits         4068     4961     +893     
+ Misses         12        9       -3     
+ Partials        8        5       -3     

Impacted Files	Coverage Δ
conf/conf.go	96.27% <100.00%> (+2.50%)	⬆️
conf/log.go	100.00% <100.00%> (ø)
eval/types.go	100.00% <100.00%> (ø)
global/easeprobe.go	100.00% <100.00%> (ø)
global/global.go	100.00% <100.00%> (ø)
notify/aws/sns.go	100.00% <100.00%> (ø)
notify/base/base.go	100.00% <100.00%> (ø)
notify/dingtalk/dingtalk.go	100.00% <100.00%> (ø)
notify/discord/discord.go	100.00% <100.00%> (ø)
notify/lark/lark.go	100.00% <100.00%> (ø)
... and 35 more

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[zhao-kun]

return strings.TrimSpace(c.Network) != "" && strings.TrimSpace(c.Host) != "" ?

[haoel]

we should avoid the negative conditionals, it's hard to read.
ref: https://moderatemisbehaviour.github.io/clean-code-smells-and-heuristics/general/g29-avoid-negative-conditionals.html