Enable lint on test sources by default (#436)

Apparently this is not enabled by default 🤦‍♂️

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slack-plugin/src/main/kotlin/slack/gradle/SlackProperties.kt

@@ -264,6 +264,14 @@ public class SlackProperties private constructor(private val project: Project) {
   public val lintBaselineFileName: String
     get() = stringProperty("slack.lint.baseline-file-name", "lint-baseline.xml")
 
+  /** Flag to control whether or not lint checks test sources. */
+  public val lintCheckTestSources: Boolean
+    get() = booleanProperty("sgp.lint.checkTestSources", true)
+
+  /** Flag to control whether or not lint checks ignores test sources. */
+  public val lintIgnoreTestSources: Boolean
+    get() = booleanProperty("sgp.lint.ignoreTestSources", false)
+
   /** Flag to enable/disable KSP. */
   public val allowKsp: Boolean
     get() = booleanProperty("slack.allow-ksp")

slack-plugin/src/main/kotlin/slack/gradle/lint/LintTasks.kt

@@ -204,6 +204,9 @@ internal object LintTasks {
     absolutePaths = false
     this.checkDependencies = checkDependencies
 
+    ignoreTestSources = slackProperties.lintIgnoreTestSources
+    checkTestSources = slackProperties.lintCheckTestSources
+
     val lintBaselineFile = slackProperties.lintBaselineFileName
 
     // Lint is weird in that it will generate a new baseline file and fail the build if a new