Remove usage of .not() where possible

(cherry picked from commit 39407407f282dbb7fa972b12053c26b3e3bd66d8)

domain/src/main/java/tachiyomi/domain/release/interactor/GetApplicationRelease.kt

@@ -20,7 +20,7 @@ class GetApplicationRelease(
         val now = Instant.now()
 
         // Limit checks to once every 3 days at most
-        if (arguments.forceCheck.not() && now.isBefore(
+        if (!arguments.forceCheck && now.isBefore(
                 Instant.ofEpochMilli(lastChecked.get()).plus(3, ChronoUnit.DAYS),
             )
         ) {

domain/src/main/java/tachiyomi/domain/source/model/StubSource.kt

@@ -22,7 +22,7 @@ class StubSource(
         throw SourceNotInstalledException()
 
     override fun toString(): String =
-        if (isInvalid.not()) "$name (${lang.uppercase()})" else id.toString()
+        if (!isInvalid) "$name (${lang.uppercase()})" else id.toString()
 
     companion object {
         fun from(source: Source): StubSource {