further bug fixes when using context path (#1475)

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

src/main/resources/templates/pdf-organizer.html

@@ -17,7 +17,7 @@
                 <span class="tool-header-text" th:text="#{pdfOrganiser.header}"></span>
               </div>
 
-              <form th:action="@{api/v1/general/rearrange-pages}" method="post" enctype="multipart/form-data">
+              <form th:action="@{'/api/v1/general/rearrange-pages'}" method="post" enctype="multipart/form-data">
                 <div th:replace="~{fragments/common :: fileSelector(name='fileInput', multiple=false, accept='application/pdf')}"></div>
                 <div class="mb-3">
                   <label for="customMode" th:text="#{pdfOrganiser.mode}">Mode</label>