Fix mergeUrlParams encoding query parameters

Before:
/-/boards/1/issues.json?page=1&per=50&scope=all&utf8=✓&state=opened&milestone_title=#upcoming

After:
 /-/boards/1/issues.json?page=1&per=50&scope=all&utf8=%E2%9C%93&state=opened&milestone_title=%23upcoming

app/assets/javascripts/lib/utils/url_utility.js

@@ -18,7 +18,7 @@ export function getParameterValues(sParam) {
 // @param {String} url
 export function mergeUrlParams(params, url) {
   let newUrl = Object.keys(params).reduce((acc, paramName) => {
-    const paramValue = params[paramName];
+    const paramValue = encodeURIComponent(params[paramName]);
     const pattern = new RegExp(`\\b(${paramName}=).*?(&|$)`);
 
     if (paramValue === null) {