[release] 1.21.0 - Option to disable ip3 country and fix potential memory leaks (#306)

New feature:
- Add option to disable ip3 country library

Fix memory leak:
- Properly close network request in multiple places
- append to existing set for exposure deduping
- Cancel coroutine work in errorBoundary when shutdown





>Included In This Release
>- f016f9a Weihao Ding
>   - revert: delete inline ip3 country look up files (#305)
>- a7fa62e tore-statsig
>   - revert: use ip3country library instead of inlined version (#304)
>- e22c18f Weihao Ding
>   - fix: cancel eb coroutine job when we shutdown (#303)
>- d042c77 Weihao Ding
>   - optimize: lazy init eb http client (#302)
>- 02d3e71 Weihao Ding
>   - clear set not re-assign the set (#299)
>- 78d28c2 tore-statsig
>   - fix: optimistically set initialized (#298)
>- bf3f1fe tore-statsig
>   - feat: add option to disable ip->country resolution (#301)
>- dea4315 tore-statsig
>   - feat: cleanup ip/country tables (#297)
>- 64c667f tore-statsig
>   - feat: inline ip3country to test fix (#296)
>- 430cc16 Weihao Ding
>   - fix: close external http client when we shutdown (#294)
>- ddc4d3e andyphan-statsig
>   - use runTest instead of runBlocking for testLogEventRetry (#292)

Author: xinlili-statsig

gradle.properties

@@ -6,7 +6,7 @@ RELEASE_SIGNING_ENABLED=true
 
 GROUP=com.statsig.serversdk
 POM_ARTIFACT_ID=serversdk
-VERSION_NAME=1.20.0
+VERSION_NAME=1.21.0
 
 POM_NAME=Statsig Server SDK
 POM_DESCRIPTION=A feature gating and a/b testing library for statsig

src/main/kotlin/com/statsig/sdk/StatsigMetadata.kt

@@ -6,7 +6,7 @@ import com.google.gson.annotations.SerializedName
 import java.util.Properties
 import java.util.UUID
 
-private const val VERSION = "1.20.0"
+private const val VERSION = "1.21.0"
 
 internal data class StatsigMetadata(@SerializedName("sdkType") var sdkType: String = "java-server", @SerializedName("sessionID") var sessionID: String = UUID.randomUUID().toString(), @SerializedName("languageVersion") var languageVersion: String = System.getProperty("java.version"), @SerializedName("exposureLoggingDisabled") var exposureLoggingDisabled: Boolean? = null) {
     @SerializedName("sdkVersion")