feat(type-scale): update type specs UI page (#1353)

* feat(type-scale): add type scale page's imagery

* feat(type-scale): update page's content & file name

* feat(type-scale): add adjusted scale table styles

* feat(type-scale): update side navigation bar title

* fix: add missing content & images

* feat: type scale picker

* feat: add images alternative-texts

* chore: minor content update

* fix: typo fix

---------

Co-authored-by: kodiakhq[bot] <49736102+kodiakhq[bot]@users.noreply.github.com>
Co-authored-by: Pavol Meszaros <[email protected]>

Author: 3 people

src/components/TypeTesterSelect/README.md

@@ -0,0 +1,31 @@
+# TypeTester
+
+## To add a new language
+
+- Add a new object to the `languageDropdownContent` array:
+
+```javascript
+const languageDropdownContent = [
+  ...,
+  ,
+  {
+    label: 'IBM Plex Sans Arabic',
+    language: 'arabic',
+    className: 'bx--type-arabic',
+    weights: commonFontWeights,
+  }
+].map(...)
+```
+
+- Add a new display text object to `languageSample` array:
+
+```javascript
+const languageSample = [
+  ...,
+  {
+    language: 'arabic',
+    content:
+      'ऋषियों को सताने वाले दुष्ट राक्षसों के राजा रावण का सर्वनाश',
+  }
+]
+```