Fix notifications pagination query parameters (#36351)

Fix #36350

services/context/pagination.go

@@ -8,8 +8,10 @@ import (
 	"html/template"
 	"net/http"
 	"net/url"
+	"slices"
 	"strings"
 
+	"code.gitea.io/gitea/modules/container"
 	"code.gitea.io/gitea/modules/paginator"
 )
 
@@ -49,6 +51,14 @@ func (p *Pagination) AddParamFromRequest(req *http.Request) {
 	p.AddParamFromQuery(req.URL.Query())
 }
 
+func (p *Pagination) RemoveParam(keys container.Set[string]) {
+	p.urlParams = slices.DeleteFunc(p.urlParams, func(s string) bool {
+		k, _, _ := strings.Cut(s, "=")
+		k, _ = url.QueryUnescape(k)
+		return keys.Contains(k)
+	})
+}
+
 // GetParams returns the configured URL params
 func (p *Pagination) GetParams() template.URL {
 	return template.URL(strings.Join(p.urlParams, "&"))