fix(boltdb): fix boltdb permissions, interval, config bugs

[rustatian]

Reason for This PR

closes: #719
closes: #718
closes: #717

Description of Changes

• Fix interval initialization
• Fix default user permissions for the boltdb file (777 -> 0777)
• Add timeout when trying to open the same boltdb file from different processes.

License Acceptance

By submitting this pull request, I confirm that my contribution is made under
the terms of the MIT license.

PR Checklist

[Author TODO: Meet these criteria.]
[Reviewer TODO: Verify that these criteria are met. Request changes if not]

• All commits in this PR are signed (git commit -s).
• The reason for this PR is clearly provided (issue no. or explanation).
• The description of changes is clear and encompassing.
• Any required documentation changes (code and docs) are included in this PR.
• Any user-facing changes are mentioned in CHANGELOG.md.
• All added/changed functionality is tested.

[codecov]

Codecov Report

Merging #724 (fe41962) into master (a38a4e6) will increase coverage by 0.18%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master     #724      +/-   ##
==========================================
+ Coverage   67.29%   67.47%   +0.18%     
==========================================
  Files          92       92              
  Lines        4797     4800       +3     
==========================================
+ Hits         3228     3239      +11     
+ Misses       1147     1143       -4     
+ Partials      422      418       -4     

Impacted Files	Coverage Δ
plugins/kv/drivers/boltdb/config.go	71.42% <100.00%> (+71.42%)	⬆️
plugins/kv/drivers/boltdb/driver.go	52.45% <100.00%> (+1.44%)	⬆️

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