feat : XssFilter String Extension 추가

- XssFilter String Extension 추가.
- 관련 테스트 코드 추가.

xss-extension-string/.gradle/buildOutputCleanup/cache.properties

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+#Tue Feb 28 14:45:48 KST 2023
+gradle.version=7.4

xss-extension-string/build.gradle

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+import org.springframework.boot.gradle.plugin.SpringBootPlugin
+
+plugins {
+    id 'org.springframework.boot' version '2.7.1' apply false
+    id 'io.spring.dependency-management' version '1.1.0'
+    id 'java'
+    id 'maven-publish'
+}
+
+group = 'com.github.xss-stage'
+version '1.1'
+
+sourceCompatibility = 1.8
+targetCompatibility = 1.8
+
+repositories {
+    mavenCentral()
+    maven {url 'https://jitpack.io'}
+}
+
+dependencyManagement {
+    imports {
+        mavenBom SpringBootPlugin.BOM_COORDINATES
+    }
+}
+
+dependencies {
+    implementation 'com.github.xss-stage:xss-core:1.1'
+
+    implementation 'com.navercorp.lucy:lucy-xss:1.6.3' // License Apache 2.0
+
+    implementation 'org.springframework.boot:spring-boot-starter'
+    testImplementation 'org.springframework.boot:spring-boot-starter-test'
+
+    testImplementation 'org.junit.jupiter:junit-jupiter-api:5.8.1'
+    testRuntimeOnly 'org.junit.jupiter:junit-jupiter-engine:5.8.1'
+}
+
+test {
+    useJUnitPlatform()
+}
+
+publishing {
+    publications {
+        maven(MavenPublication) {
+            from components.java
+        }
+    }
+}
+
+wrapper {
+    gradleVersion = "7.3.3"
+    distributionType = Wrapper.DistributionType.ALL
+}

xss-extension-string/gradle/wrapper/gradle-wrapper.properties

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+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-7.4-bin.zip
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists