Fix System Requirements URL and typo in hardware warnings

Fixes QubesOS/qubes-issues#3932
Related to QubesOS/qubes-issues#3208

anaconda/pyanaconda/ui/gui/spokes/welcome.glade

@@ -507,7 +507,7 @@
                 <property name="visible">True</property>
                 <property name="can_focus">False</property>
                 <property name="valign">start</property>
-                <property name="label" translatable="yes">This hardware lacks features required by Qubes OS. Missing features: %(features)s. Without these features, Qubes OS will not function normally. It is recommended that only developers and power users proceed with the installation. For more information on supported hardware, please refer to https://www.qubes-os.org/system-requirements/</property>
+                <property name="label" translatable="yes">This hardware lacks features required by Qubes OS. Missing features: %(features)s. Without these features, Qubes OS will not function normally. It is recommended that only developers and power users proceed with the installation. For more information on supported hardware, please refer to https://www.qubes-os.org/doc/system-requirements/</property>
                 <property name="wrap">True</property>
                 <attributes>
                   <attribute name="font-desc" value="Cantarell 12"/>

anaconda/pyanaconda/ui/tui/spokes/warnings_spoke.py

@@ -43,10 +43,10 @@ class WarningsSpoke(StandaloneTUISpoke):
     def __init__(self, *args, **kwargs):
         StandaloneTUISpoke.__init__(self, *args, **kwargs)
 
-        self._message = _("This hardware lack features required by Qubes OS. "
+        self._message = _("This hardware lacks features required by Qubes OS. "
                           "Missing features: %(features)s. "
                           "For more information on supported hardware, "
-                          "please refer to https://www.qubes-os.org/system-requirements/")
+                          "please refer to https://www.qubes-os.org/doc/system-requirements/")
         # Does anything need to be displayed?
         # pylint: disable=no-member
         #   self._unsupported = not self.data.unsupportedhardware.unsupported_hardware \