Set immutable variables as final

[amdelamar]

No description provided.

[codecov]

Codecov Report

Merging #23 into master will not change coverage.
The diff coverage is 91.66%.

@@            Coverage Diff            @@
##             master      #23   +/-   ##
=========================================
  Coverage     94.48%   94.48%           
  Complexity       46       46           
=========================================
  Files             5        5           
  Lines           127      127           
  Branches         21       21           
=========================================
  Hits            120      120           
  Misses            7        7           

Impacted Files	Coverage Δ	Complexity Δ
src/main/java/com/amdelamar/jotp/OTP.java	89.39% <87.50%> (ø)	20.00 <3.00> (ø)
src/main/java/com/amdelamar/jotp/type/HOTP.java	100.00% <100.00%> (ø)	16.00 <0.00> (ø)
src/main/java/com/amdelamar/jotp/type/TOTP.java	100.00% <100.00%> (ø)	8.00 <2.00> (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 4cc90e1...d174ea5. Read the comment docs.