Permission default value

I created a permission with the following code:
```groovy
permission 'surredstone.village', {
description 'Executar o comando /village.'
allow ALL
}
```

And the result in the file ``plugin.yml`` was this:
```yml
surredstone.village: {default: 'true', description: Executar o comando /village.}
```
The ``default`` value was set to ``'true'`` instead of ``true``
The ``OPERATOR`` and ``NOT_OPERATOR`` values doesn't appear to have any problem.

I'm new in the Java environment and don't understand very much about the building process, so, if I'm doing something wrong please warn me!

- Using PaperMC, it threw the following error:
```error
[20:30:04 ERROR]: Could not load 'plugins\Surredstone.jar' in folder 'plugins'
org.bukkit.plugin.InvalidDescriptionException: Invalid plugin.yml
at org.bukkit.plugin.java.JavaPluginLoader.getPluginDescription(JavaPluginLoader.java:188) ~[paper-api-1.18.2-R0.1-SNAPSHOT.jar:?]
at org.bukkit.plugin.SimplePluginManager.loadPlugins(SimplePluginManager.java:159) ~[paper-api-1.18.2-R0.1-SNAPSHOT.jar:?]
at org.bukkit.craftbukkit.v1_18_R2.CraftServer.loadPlugins(CraftServer.java:417) ~[paper-1.18.2.jar:git-Paper-260]
at net.minecraft.server.dedicated.DedicatedServer.initServer(DedicatedServer.java:288) ~[paper-1.18.2.jar:git-Paper-260]
at net.minecraft.server.MinecraftServer.runServer(MinecraftServer.java:1163)
~[paper-1.18.2.jar:git-Paper-260]
at net.minecraft.server.MinecraftServer.lambda$spin$0(MinecraftServer.java:315) ~[paper-1.18.2.jar:git-Paper-260]
at java.lang.Thread.run(Thread.java:833) ~[?:?]
Caused by: org.yaml.snakeyaml.error.YAMLException: java.nio.charset.MalformedInputException: Input length = 1
at org.yaml.snakeyaml.reader.StreamReader.update(StreamReader.java:218) ~[snakeyaml-1.30.jar:?]
at org.yaml.snakeyaml.reader.StreamReader.ensureEnoughData(StreamReader.java:176) ~[snakeyaml-1.30.jar:?]
at org.yaml.snakeyaml.reader.StreamReader.ensureEnoughData(StreamReader.java:171) ~[snakeyaml-1.30.jar:?]
at org.yaml.snakeyaml.reader.StreamReader.peek(StreamReader.java:126) ~[snakeyaml-1.30.jar:?]
at org.yaml.snakeyaml.scanner.ScannerImpl.scanToNextToken(ScannerImpl.java:1218) ~[snakeyaml-1.30.jar:?]
at org.yaml.snakeyaml.scanner.ScannerImpl.fetchMoreTokens(ScannerImpl.java:329) ~[snakeyaml-1.30.jar:?]
at org.yaml.snakeyaml.scanner.ScannerImpl.checkToken(ScannerImpl.java:251) ~[snakeyaml-1.30.jar:?]
at org.yaml.snakeyaml.parser.ParserImpl$ParseImplicitDocumentStart.produce(ParserImpl.java:214) ~[snakeyaml-1.30.jar:?]
at org.yaml.snakeyaml.parser.ParserImpl.peekEvent(ParserImpl.java:166) ~[snakeyaml-1.30.jar:?]
at org.yaml.snakeyaml.parser.ParserImpl.checkEvent(ParserImpl.java:156) ~[snakeyaml-1.30.jar:?]
at org.yaml.snakeyaml.composer.Composer.getSingleNode(Composer.java:141) ~[snakeyaml-1.30.jar:?]
at org.yaml.snakeyaml.constructor.BaseConstructor.getSingleData(BaseConstructor.java:151) ~[snakeyaml-1.30.jar:?]
at org.yaml.snakeyaml.Yaml.loadFromReader(Yaml.java:491) ~[snakeyaml-1.30.jar:?]
at org.yaml.snakeyaml.Yaml.load(Yaml.java:429) ~[snakeyaml-1.30.jar:?]
at org.bukkit.plugin.PluginDescriptionFile.(PluginDescriptionFile.java:259) ~[paper-api-1.18.2-R0.1-SNAPSHOT.jar:?]
at org.bukkit.plugin.java.JavaPluginLoader.getPluginDescription(JavaPluginLoader.java:183) ~[paper-api-1.18.2-R0.1-SNAPSHOT.jar:?]
... 6 more
Caused by: java.nio.charset.MalformedInputException: Input length = 1
at java.nio.charset.CoderResult.throwException(CoderResult.java:274) ~[?:?]
at sun.nio.cs.StreamDecoder.implRead(StreamDecoder.java:326) ~[?:?]
at sun.nio.cs.StreamDecoder.read(StreamDecoder.java:188) ~[?:?]
at java.io.InputStreamReader.read(InputStreamReader.java:177) ~[?:?]
at org.yaml.snakeyaml.reader.UnicodeReader.read(UnicodeReader.java:125) ~[snakeyaml-1.30.jar:?]
at org.yaml.snakeyaml.reader.StreamReader.update(StreamReader.java:183) ~[snakeyaml-1.30.jar:?]
at org.yaml.snakeyaml.reader.StreamReader.ensureEnoughData(StreamReader.java:176) ~[snakeyaml-1.30.jar:?]
at org.yaml.snakeyaml.reader.StreamReader.ensureEnoughData(StreamReader.java:171) ~[snakeyaml-1.30.jar:?]
at org.yaml.snakeyaml.reader.StreamReader.peek(StreamReader.java:126) ~[snakeyaml-1.30.jar:?]
at org.yaml.snakeyaml.scanner.ScannerImpl.scanToNextToken(ScannerImpl.java:1218) ~[snakeyaml-1.30.jar:?]
at org.yaml.snakeyaml.scanner.ScannerImpl.fetchMoreTokens(ScannerImpl.java:329) ~[snakeyaml-1.30.jar:?]
at org.yaml.snakeyaml.scanner.ScannerImpl.checkToken(ScannerImpl.java:251) ~[snakeyaml-1.30.jar:?]
at org.yaml.snakeyaml.parser.ParserImpl$ParseImplicitDocumentStart.produce(ParserImpl.java:214) ~[snakeyaml-1.30.jar:?]
at org.yaml.snakeyaml.parser.ParserImpl.peekEvent(ParserImpl.java:166) ~[snakeyaml-1.30.jar:?]
at org.yaml.snakeyaml.parser.ParserImpl.checkEvent(ParserImpl.java:156) ~[snakeyaml-1.30.jar:?]
at org.yaml.snakeyaml.composer.Composer.getSingleNode(Composer.java:141) ~[snakeyaml-1.30.jar:?]
at org.yaml.snakeyaml.constructor.BaseConstructor.getSingleData(BaseConstructor.java:151) ~[snakeyaml-1.30.jar:?]
at org.yaml.snakeyaml.Yaml.loadFromReader(Yaml.java:491) ~[snakeyaml-1.30.jar:?]
at org.yaml.snakeyaml.Yaml.load(Yaml.java:429) ~[snakeyaml-1.30.jar:?]
at org.bukkit.plugin.PluginDescriptionFile.(PluginDescriptionFile.java:259) ~[paper-api-1.18.2-R0.1-SNAPSHOT.jar:?]
at org.bukkit.plugin.java.JavaPluginLoader.getPluginDescription(JavaPluginLoader.java:183) ~[paper-api-1.18.2-R0.1-SNAPSHOT.jar:?]
... 6 more
```

Start by tracing the permission DSL that produces plugin.yml, then inspect how the default value is serialized. Reproduce the shown allow ALL case and verify that the generated YAML uses a boolean true and that Paper can load it without the reported error.

Written by the indexing model from the issue text.