Try to improve consistency

- Makes code formatting more consistent with the C++ codebase. Probably removes some trailing whitespace. Maybe it would be best to commit an Eclipse or IntelliJ code format preferences file?
- Removes obscure suppressions. I personally think it's better to only suppress warnings that javac complains about. Suppressing a lot of non-standardised warnings (many of them turned off by default even in IntelliJ) just creates needless clutter.
- Fixes some trivial warnings instead of suppressing them. serialVersionUID is sort of stupid, but I'd rather mentally ignore it or just fix it if it's really that annoying.

Signed-off-by: TheKodeToad <TheKodeToad@proton.me>

libraries/launcher/org/prismlauncher/launcher/impl/legacy/LegacyFrame.java

@@ -57,7 +57,6 @@
 
 package org.prismlauncher.launcher.impl.legacy;
 
-
 import net.minecraft.Launcher;
 
 import javax.imageio.ImageIO;
@@ -77,7 +76,7 @@ import java.util.List;
 import java.util.logging.Level;
 import java.util.logging.Logger;
 
-public final class LegacyFrame extends Frame {
+public final class LegacyFrame extends Frame /* TODO consider JFrame */ {
 
     private static final Logger LOGGER = Logger.getLogger("LegacyFrame");
 
@@ -163,7 +162,7 @@ public final class LegacyFrame extends Frame {
         setResizable(true);
 
         if (maximize)
-            this.setExtendedState(MAXIMIZED_BOTH);
+            setExtendedState(MAXIMIZED_BOTH);
 
         validate();