adding db url in the connection exception

[peeyush18]

Hi @brettwooldridge

I am adding some extra data to the connection exception.

During getting a connection it is becomes hard to debug and troubleshoot. In case of multiple db servers(replicas) the change will help in isolating the server/s stalling while connecting

[codecov]

Codecov Report

Merging #2010 (8f15507) into dev (d92b50f) will decrease coverage by 0.38%.
The diff coverage is 100.00%.

@@             Coverage Diff              @@
##                dev    #2010      +/-   ##
============================================
- Coverage     70.79%   70.40%   -0.39%     
+ Complexity      575      571       -4     
============================================
  Files            26       26              
  Lines          2164     2166       +2     
  Branches        311      311              
============================================
- Hits           1532     1525       -7     
- Misses          480      488       +8     
- Partials        152      153       +1     

Impacted Files	Coverage Δ
...c/main/java/com/zaxxer/hikari/pool/HikariPool.java	81.26% <100.00%> (+0.11%)	⬆️
...ain/java/com/zaxxer/hikari/util/ConcurrentBag.java	73.40% <0.00%> (-3.20%)	⬇️
src/main/java/com/zaxxer/hikari/pool/PoolBase.java	70.43% <0.00%> (-2.19%)	⬇️

---

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 d92b50f...8f15507. Read the comment docs.