REFACTOR: add parameter index to the Last method

[c9s]

The goal is to replace Index(i) with Last(i) to simplify the interface

[bbgokarma-bot]

Welcome back! @c9s, This pull request may get 1483 BBG.

[codecov]

Codecov Report

Merging #1182 (5515f58) into main (2a074ba) will increase coverage by 0.00%.
The diff coverage is 46.93%.

@@           Coverage Diff            @@
##             main    #1182    +/-   ##
========================================
  Coverage   20.85%   20.85%            
========================================
  Files         490      493     +3     
  Lines       34985    34810   -175     
========================================
- Hits         7295     7259    -36     
+ Misses      27120    26996   -124     
+ Partials      570      555    -15     

Impacted Files	Coverage Δ
pkg/bbgo/exit_lower_shadow_take_profit.go	0.00% <0.00%> (ø)
pkg/bbgo/stop_ema.go	0.00% <0.00%> (ø)
pkg/bbgo/trend_ema.go	11.76% <0.00%> (ø)
pkg/datatype/floats/slice.go	28.00% <0.00%> (ø)
pkg/indicator/ad.go	0.00% <0.00%> (ø)
pkg/indicator/atrp.go	0.00% <0.00%> (ø)
pkg/indicator/cma.go	0.00% <0.00%> (ø)
pkg/indicator/fisher.go	0.00% <0.00%> (ø)
pkg/indicator/klingeroscillator.go	62.00% <0.00%> (+5.63%)	⬆️
pkg/indicator/line.go	0.00% <0.00%> (ø)
... and 61 more

---

Continue to review full report in Codecov by Sentry.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 2a074ba...5515f58. Read the comment docs.

[bbgokarma-bot]

Hi @c9s,

Well done! 1493 BBG has been sent to your polygon wallet. Please check the following tx:

https://polygonscan.com/tx/0x40031c76e9624199dec80ec684a57b6280fc2552a1f20c83e108ce50e9ad3a09

Thank you for your contribution!