Add extended tips for slant&corner radius tab page

Control points 1 and 2.

Change-Id: Ia932b6d938831fffb374db24e2c7906e1eb6db18
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/103484
Tested-by: Jenkins
Reviewed-by: Olivier Hallot <olivier.hallot@libreoffice.org>
diff --git a/cui/uiconfig/ui/slantcornertabpage.ui b/cui/uiconfig/ui/slantcornertabpage.ui
index d096737..83edff2 100644
--- a/cui/uiconfig/ui/slantcornertabpage.ui
+++ b/cui/uiconfig/ui/slantcornertabpage.ui
@@ -85,6 +85,11 @@
                        <property name="activates_default">True</property>
                        <property name="adjustment">adjustment1</property>
                        <property name="digits">2</property>
                        <child internal-child="accessible">
                          <object class="AtkObject" id="controlx1-atkobject">
                            <property name="AtkObject::accessible-description" translatable="yes" context="slantcornertabpage|extended_tip|controlx1">Enter the X coordinate of the control point 1</property>
                          </object>
                        </child>
                      </object>
                      <packing>
                        <property name="expand">False</property>
@@ -125,6 +130,11 @@
                        <property name="activates_default">True</property>
                        <property name="adjustment">adjustment3</property>
                        <property name="digits">2</property>
                        <child internal-child="accessible">
                          <object class="AtkObject" id="controly1-atkobject">
                            <property name="AtkObject::accessible-description" translatable="yes" context="slantcornertabpage|extended_tip|controly1">Enter the Y coordinate of the control point 1</property>
                          </object>
                        </child>
                      </object>
                      <packing>
                        <property name="expand">False</property>
@@ -345,6 +355,11 @@
                        <property name="activates_default">True</property>
                        <property name="adjustment">adjustment2</property>
                        <property name="digits">2</property>
                        <child internal-child="accessible">
                          <object class="AtkObject" id="controlx2-atkobject">
                            <property name="AtkObject::accessible-description" translatable="yes" context="slantcornertabpage|extended_tip|controlx2">Enter the X coordinate of the control point 2</property>
                          </object>
                        </child>
                      </object>
                      <packing>
                        <property name="expand">False</property>
@@ -385,6 +400,11 @@
                        <property name="activates_default">True</property>
                        <property name="adjustment">adjustment4</property>
                        <property name="digits">2</property>
                        <child internal-child="accessible">
                          <object class="AtkObject" id="controly2-atkobject">
                            <property name="AtkObject::accessible-description" translatable="yes" context="slantcornertabpage|extended_tip|controly2">Enter the Y coordinate of the control point 2</property>
                          </object>
                        </child>
                      </object>
                      <packing>
                        <property name="expand">False</property>