fix oracle.bot.ts failing to publish due to lower than 0 price

[fuxingloh]

What kind of PR is this?:

/kind fix

[codeclimate]

Code Climate has analyzed commit ecd1bb7 and detected 0 issues on this pull request.

View more on Code Climate.

[codecov]

Codecov Report

Merging #295 (ecd1bb7) into main (3c3faad) will increase coverage by 0.39%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main     #295      +/-   ##
==========================================
+ Coverage   81.71%   82.10%   +0.39%     
==========================================
  Files          40       41       +1     
  Lines         733      749      +16     
  Branches       66       67       +1     
==========================================
+ Hits          599      615      +16     
  Misses        134      134              

Impacted Files	Coverage Δ
src/module.playground/_module.ts	93.61% <100.00%> (+0.13%)	⬆️
src/module.playground/bot/oracle.bot.ts	90.69% <100.00%> (ø)
src/module.playground/bot/vault.bot.ts	100.00% <100.00%> (ø)

---

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 a82f6b1...ecd1bb7. Read the comment docs.