[grubcfg] Add some test configurations

src/modules/grubcfg/tests/1.global

@@ -0,0 +1,2 @@
+---
+bogus: true

src/modules/grubcfg/tests/2.global

@@ -0,0 +1,10 @@
+---
+bogus: true
+firmwareType: bios
+bootLoader: grub
+rootMountPoint: /tmp/calamares
+
+branding:
+  bootloaderEntryName: generic
+partitions: []
+

src/modules/grubcfg/tests/2.job

@@ -0,0 +1,9 @@
+---
+overwrite: true
+keepDistributor: false
+defaults:
+    GRUB_TIMEOUT: 5
+    GRUB_DEFAULT: "saved"
+    GRUB_DISABLE_SUBMENU: true
+    GRUB_TERMINAL_OUTPUT: "console"
+    GRUB_DISABLE_RECOVERY: true