Fix deprecation warnings

Author: adrw

client-sqldelight-gradle-plugin/src/test/projects/happyPath/lib/build.gradle.kts

@@ -13,7 +13,7 @@ sqldelight {
       dialect(libs.sqldelightMysqlDialect)
       srcDirs.setFrom(listOf("resources/migrations"))
       deriveSchemaFromMigrations.set(true)
-      migrationOutputDirectory.set(file("$buildDir/resources/main/migrations"))
+      migrationOutputDirectory.set(layout.buildDirectory.dir("resources/main/migrations"))
       verifyMigrations.set(true)
     }
   }

client-sqldelight-test/build.gradle.kts

@@ -12,7 +12,7 @@ sqldelight {
       dialect(libs.sqldelightMysqlDialect)
       srcDirs.setFrom(listOf("src/main/sqldelight", "src/main/resources/migrations"))
       deriveSchemaFromMigrations.set(true)
-      migrationOutputDirectory.set(file("${buildDir}/resources/main/migrations"))
+      migrationOutputDirectory.set(layout.buildDirectory.dir("resources/main/migrations"))
       verifyMigrations.set(true)
     }
   }

client/build.gradle.kts

@@ -11,7 +11,7 @@ plugins {
 
 sourceSets {
   val main by getting {
-    java.srcDir("$buildDir/generated/source/wire/")
+    java.srcDir(layout.buildDirectory.dir("generated/source/wire"))
   }
 }