"feat: update build.gradle to use GitHub repository ref and version"

This commit message clearly states the main action taken in the code, which is updating the `build.gradle` file to include the GitHub repository reference and version. It also provides context with a more detailed description, while keeping it concise.

Author: kdroidFilter

build.gradle.kts

@@ -10,7 +10,11 @@ plugins {
 }
 
 group = "com.kdroid.composenativetray"
-version = "0.6.1"
+val ref = System.getenv("GITHUB_REF") ?: ""
+val version = if (ref.startsWith("refs/tags/")) {
+    val tag = ref.removePrefix("refs/tags/")
+    if (tag.startsWith("v")) tag.substring(1) else tag
+} else "dev"
 
 repositories {
     mavenCentral()