Use common-utils from maven, use withContext instead runBlocking

[skkosuri-amzn]

Issue #, if available:

1. Use common-utils from maven,
2. use withContext instead runBlocking

Description of changes:
On #2
https://kotlin.github.io/kotlinx.coroutines/kotlinx-coroutines-core/kotlinx.coroutines/run-blocking.html
runBlocking: blocks the current thread interruptibly until its completion
withContext : Calls the specified suspending block with a given coroutine context, suspends until it completes, and returns the result.

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[codecov]

Codecov Report

Merging #273 into master will decrease coverage by 0.09%.
The diff coverage is 100.00%.

@@             Coverage Diff              @@
##             master     #273      +/-   ##
============================================
- Coverage     79.92%   79.83%   -0.10%     
+ Complexity      195      194       -1     
============================================
  Files           150      150              
  Lines          5132     5132              
  Branches        661      661              
============================================
- Hits           4102     4097       -5     
- Misses          666      668       +2     
- Partials        364      367       +3     

Impacted Files	Coverage Δ	Complexity Δ
...endistroforelasticsearch/alerting/MonitorRunner.kt	76.31% <100.00%> (ø)	0.00 <0.00> (ø)
...distroforelasticsearch/alerting/core/JobSweeper.kt	69.51% <0.00%> (-2.68%)	34.00% <0.00%> (-1.00%)

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