Don't use an arrow icon for calendar navigation submit button

src/pretix/presale/templates/pretixpresale/event/fragment_subevent_calendar.html

@@ -37,7 +37,7 @@
                         </select>
                         <span class="input-group-btn">
                             <button type="submit" class="btn btn-default" aria-label="{% trans "Show month" %}">
-                                {% icon "chevron-right" %}
+                                {% icon "check" %}
                             </button>
                         </span>
                     </div>

src/pretix/presale/templates/pretixpresale/event/fragment_subevent_calendar_week.html

@@ -41,7 +41,7 @@
                         </select>
                         <span class="input-group-btn">
                             <button type="submit" class="btn btn-default" aria-label="{% trans "Show week" %}">
-                                {% icon "chevron-right" %}
+                                {% icon "check" %}
                             </button>
                         </span>
                     </div>

src/pretix/presale/templates/pretixpresale/organizers/calendar.html

@@ -69,7 +69,7 @@
                                     </select>
                                     <span class="input-group-btn">
                                         <button type="submit" class="btn btn-default" aria-label="{% trans "Show month" %}">
-                                            {% icon "chevron-right" %}
+                                            {% icon "check" %}
                                         </button>
                                     </span>
                                 </div>

src/pretix/presale/templates/pretixpresale/organizers/calendar_day.html

@@ -61,7 +61,7 @@
                                     <input class="datepickerfield form-control" id="calendar-input-date" value="{{ date|date:"SHORT_DATE_FORMAT" }}" name="date">
                                     <span class="input-group-btn">
                                         <button type="submit" class="btn btn-default" aria-label="{% trans "Show date" %}">
-                                            {% icon "chevron-right" %}
+                                            {% icon "check" %}
                                         </button>
                                     </span>
                                 </div>

src/pretix/presale/templates/pretixpresale/organizers/calendar_week.html

@@ -73,7 +73,7 @@
                                     </select>
                                     <span class="input-group-btn">
                                         <button type="submit" class="btn btn-default" aria-label="{% trans "Show week" %}">
-                                            {% icon "chevron-right" %}
+                                            {% icon "check" %}
                                         </button>
                                     </span>
                                 </div>