minor typo fix for ExecutorService

[jasonoh]

This is a single, minor spelling fix. No code changes.

Category (place an x in each of the [ ])

• [x ] bolt (Bolt for Java)
• bolt-{sub modules} (Bolt for Java - optional modules)
• slack-api-client (Slack API Clients)
• slack-api-model (Slack API Data Models)
• slack-api-*-kotlin-extension (Kotlin Extensions for Slack API Clients)
• slack-app-backend (The primitive layer of Bolt for Java)

Requirements

Please read the Contributing guidelines and Code of Conduct before creating this issue or pull request. By submitting, you agree to those rules.

[srajiang]

Nice, thanks for the fix @jasonoh!

[jasonoh]

my pleasure, @srajiang! 😄

[codecov]

Codecov Report

Merging #1073 (de1db1d) into main (3cfdea5) will increase coverage by 0.01%.
The diff coverage is n/a.

❗ Current head de1db1d differs from pull request most recent head b54d092. Consider uploading reports for the commit b54d092 to get more accurate results

@@             Coverage Diff              @@
##               main    #1073      +/-   ##
============================================
+ Coverage     76.74%   76.76%   +0.01%     
- Complexity     3761     3763       +2     
============================================
  Files           409      409              
  Lines         11402    11402              
  Branches       1150     1150              
============================================
+ Hits           8751     8753       +2     
+ Misses         1961     1960       -1     
+ Partials        690      689       -1     

Impacted Files	Coverage Δ
...imits/metrics/impl/BaseMemoryMetricsDatastore.java	80.08% <0.00%> (+0.43%)	⬆️
...va/com/slack/api/socket_mode/SocketModeClient.java	64.33% <0.00%> (+0.63%)	⬆️

📣 We’re building smart automated test selection to slash your CI/CD build times. Learn more