Fix DataConverter ConverterParticleToNBT.parseProperties

- The old code was using `StringReader.peek()` in a place where it meant to be `StringReader.skip()`.
- The vanilla code allows a trailing comma, but only if there is no whitespace between it and the closing bracket, which is a bit weird. I think that's a bug and it shouldn't allow trailing commas, but if you disagree then only the first issue needs to be fixed.

patches/server/0976-Rewrite-dataconverter-system.patch

@@ -7908,10 +7908,10 @@ index 0000000000000000000000000000000000000000..769dd8447976b66dcfc36283ede4ae16
 +}
 diff --git a/src/main/java/ca/spottedleaf/dataconverter/minecraft/converters/particle/ConverterParticleToNBT.java b/src/main/java/ca/spottedleaf/dataconverter/minecraft/converters/particle/ConverterParticleToNBT.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..0f961bca2ab2cd9e93cb7c23951ac6b867cdd04e
+index 0000000000000000000000000000000000000000..2cf90187ea8bc54b06cebd54ae2582ca66d91132
 --- /dev/null
 +++ b/src/main/java/ca/spottedleaf/dataconverter/minecraft/converters/particle/ConverterParticleToNBT.java
-@@ -0,0 +1,268 @@
+@@ -0,0 +1,270 @@
 +package ca.spottedleaf.dataconverter.minecraft.converters.particle;
 +
 +import ca.spottedleaf.dataconverter.types.ListType;
@@ -7970,27 +7970,29 @@ index 0000000000000000000000000000000000000000..0f961bca2ab2cd9e93cb7c23951ac6b8
 +            reader.expect('[');
 +            reader.skipWhitespace();
 +
-+            while (reader.canRead() && reader.peek() != ']') {
++            if (reader.canRead() && reader.peek() != ']') {
-+                reader.skipWhitespace();
++                while (reader.canRead()) {
-+
++                    final String property = reader.readString();
-+                final String property = reader.readString();
++    
-+
++                    reader.skipWhitespace();
-+                reader.skipWhitespace();
++                    reader.expect('=');
-+                reader.expect('=');
++                    reader.skipWhitespace();
-+                reader.skipWhitespace();
++    
-+
++                    final String value = reader.readString();
-+                final String value = reader.readString();
++                    ret.setString(property, value);
-+                ret.setString(property, value);
++    
-+
++                    reader.skipWhitespace();
-+                reader.skipWhitespace();
++                    if (reader.canRead()) {
-+                if (reader.canRead()) {
++                        if (reader.peek() != ',') {
-+                    if (reader.peek() != ',') {
++                            // invalid character or ']'
-+                        // invalid character or ']'
++                            break;
-+                        break;
++                        }
++    
++                        // skip ',' and move onto next entry
++                        reader.skip();
 +                    }
-+
++                    
-+                    // skip ',' and move onto next entry
++                    reader.skipWhitespace();
-+                    reader.peek();
 +                }
 +            }
 +
@@ -22437,7 +22439,7 @@ index 0000000000000000000000000000000000000000..f50b81d931a1908d405bb72e0679983a
 +}
 diff --git a/src/main/java/ca/spottedleaf/dataconverter/minecraft/versions/V3818.java b/src/main/java/ca/spottedleaf/dataconverter/minecraft/versions/V3818.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..29d256c2f5d5e338dc7abeb82c0f1ae99ee1edf7
+index 0000000000000000000000000000000000000000..40f9b8f2a3d0b01dc97472f34c441321a0e33079
 --- /dev/null
 +++ b/src/main/java/ca/spottedleaf/dataconverter/minecraft/versions/V3818.java
 @@ -0,0 +1,339 @@