fix: Add MultiTool UploadPrompts zh_CN And en_US (#977)

Co-authored-by: superfan <admin@henniubi.com>
Co-authored-by: Anthony Stirling <77850077+Frooodle@users.noreply.github.com>

src/main/resources/messages_en_US.properties

@@ -775,6 +775,7 @@ pdfOrganiser.placeholder=(e.g. 1,3,2 or 4-8,2,10-12 or 2n-1)
 #multiTool
 multiTool.title=PDF Multi Tool
 multiTool.header=PDF Multi Tool
+multiTool.uploadPrompts=Please Upload PDF
 
 #view pdf
 viewPdf.title=View PDF

src/main/resources/messages_zh_CN.properties

@@ -775,6 +775,7 @@ pdfOrganiser.placeholder=（例如 1,3,2 或 4-8,2,10-12 或 2n-1）
 #multiTool
 multiTool.title=PDF多功能工具
 multiTool.header=PDF多功能工具
+multiTool.uploadPrompts=上传PDF
 
 #view pdf
 viewPdf.title=浏览PDF

src/main/resources/templates/multi-tool.html

@@ -30,8 +30,8 @@
             <div class="col-md-6" style="text-align: center">
               <div class="global-buttons-container d-flex align-content-center justify-content-center">
                 <div class="form-group">
-                  <label for="filename-input" th:text="#{multiTool.filename}">Filename</label>
-                  <input type="text" class="form-control" id="filename-input" th:placeholder="#{multiTool.filename}">
+                  <label for="filename-input" th:text="#{multiTool.uploadPrompts}">Filename</label>
+                  <input type="text" class="form-control" id="filename-input" th:placeholder="#{multiTool.uploadPrompts}">
                 </div>
               </div>
               <div class="global-buttons-container">