Add the observable10 qualitative colormap (#67)

* Add the `observable10` qualitative colormap

* style(pre-commit.ci): auto fixes [...]

* Update record.json

* Update record.json

* Update record.json

---------

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: Talley Lambert <talley.lambert@gmail.com>

src/cmap/data/observable/__init__.py

@@ -0,0 +1,12 @@
+observable10 = [
+    [66, 105, 208],  # 4269D0
+    [239, 177, 24],  # EFB118
+    [255, 114, 92],  # FF725C
+    [108, 197, 176],  # 6CC5B0
+    [60, 169, 81],  # 3CA951
+    [255, 138, 183],  # FF8AB7
+    [164, 99, 242],  # A463F2
+    [151, 187, 245],  # 97BBF5
+    [156, 107, 78],  # 9C6B4E
+    [148, 152, 160],  # 9498A0
+]

src/cmap/data/observable/record.json

@@ -0,0 +1,17 @@
+{
+  "authors": [],
+  "colormaps": {
+    "observable10": {
+      "authors": [
+        "Jeff Pettiross"
+      ],
+      "category": "qualitative",
+      "data": "cmap.data.observable:observable10",
+      "info": "A categorical palette with ten colors designed for Observable Plot library. See <https://observablehq.com/blog/crafting-data-colors> for more information.",
+      "interpolation": false
+    }
+  },
+  "license": "Apache-2.0",
+  "namespace": "observable",
+  "source": "https://github.com/d3/d3-scale-chromatic"
+}