Fix for problems when a nullable parameter has a default value

When a default value is present the parameter is moved to non-nullable. This works because we could replace the null with a default value. This will actually set the default value.

Author: koenlavooij

modules/openapi-generator/src/main/resources/kotlin-server/libraries/javalin5/pathParams.mustache

@@ -1 +1 @@
-{{#isPathParam}}ctx.pathParamAsClass<{{{dataType}}}>("{{baseName}}").get(){{/isPathParam}}
+{{#isPathParam}}ctx.pathParamAsClass<{{{dataType}}}>("{{baseName}}").get(){{>paramDefault}}{{/isPathParam}}

modules/openapi-generator/src/main/resources/kotlin-server/libraries/javalin5/queryParams.mustache

@@ -1 +1 @@
-{{#isQueryParam}}{{#isArray}}ctx.queryParams("{{baseName}}"){{/isArray}}{{^isArray}}ctx.queryParamAsClass<String>("{{baseName}}").get(){{/isArray}}{{/isQueryParam}}
+{{#isQueryParam}}{{#isArray}}ctx.queryParams("{{baseName}}"){{/isArray}}{{^isArray}}ctx.queryParamAsClass<String>("{{baseName}}").get(){{>paramDefault}}{{/isArray}}{{/isQueryParam}}

modules/openapi-generator/src/main/resources/kotlin-server/libraries/javalin6/pathParams.mustache

@@ -1 +1 @@
-{{#isPathParam}}ctx.pathParamAsClass<{{{dataType}}}>("{{baseName}}").get(){{/isPathParam}}
+{{#isPathParam}}ctx.pathParamAsClass<{{{dataType}}}>("{{baseName}}").get(){{>paramDefault}}{{/isPathParam}}

modules/openapi-generator/src/main/resources/kotlin-server/libraries/javalin6/queryParams.mustache

@@ -1 +1 @@
-{{#isQueryParam}}{{#isArray}}ctx.queryParams("{{baseName}}"){{/isArray}}{{^isArray}}ctx.queryParamAsClass<{{{dataType}}}>("{{baseName}}"){{^required}}.allowNullable(){{/required}}.get(){{/isArray}}{{/isQueryParam}}
+{{#isQueryParam}}{{#isArray}}ctx.queryParams("{{baseName}}"){{/isArray}}{{^isArray}}ctx.queryParamAsClass<{{{dataType}}}>("{{baseName}}"){{^required}}.allowNullable(){{/required}}.get(){{>paramDefault}}{{/isArray}}{{/isQueryParam}}