Remove org.jetbrains.annotations dependency

Its no longer needed, it was used for only a single @NotNull and its a redundant annotation at that.

core/src/main/java/org/dreamexposure/discal/core/calendar/CalendarAuth.java

@@ -11,7 +11,6 @@ import org.dreamexposure.discal.core.entities.google.DisCalGoogleCredential;
 import org.dreamexposure.discal.core.network.google.Authorization;
 import org.dreamexposure.discal.core.object.BotSettings;
 import org.dreamexposure.discal.core.object.calendar.CalendarData;
-import org.jetbrains.annotations.NotNull;
 import reactor.core.publisher.Flux;
 import reactor.core.publisher.Mono;
 import reactor.core.scheduler.Schedulers;
@@ -74,7 +73,7 @@ public class CalendarAuth {
             .switchIfEmpty(Mono.error(new IllegalStateException("Empty not allowed")));
     }
 
-    public static Mono<Calendar> getCalendarService(@NotNull CalendarData calData) {
+    public static Mono<Calendar> getCalendarService(CalendarData calData) {
         return Mono.fromCallable(() -> {
             if (calData.getExternal()) {
                 return authorize(calData).map(cred ->

core/src/main/java/org/dreamexposure/discal/core/utils/ChannelUtils.java

@@ -49,4 +49,4 @@ public class ChannelUtils {
         return getChannelFromNameOrId(nameOrId, guild)
             .map(GuildMessageChannel::getName);
     }
-}
+}

pom.xml

@@ -124,12 +124,6 @@
             <version>${kotlinx.serialization.version}</version>
             <type>pom</type>
         </dependency>
-        <!--For Annotations-->
-        <dependency>
-            <groupId>org.jetbrains</groupId>
-            <artifactId>annotations</artifactId>
-            <version>20.1.0</version>
-        </dependency>
         <!-- slf4j-api - Need to force this for logback to work. I dunno -->
         <dependency>
             <groupId>org.slf4j</groupId>