chore(repo): Move supplementary data to data dir

Since we now have a 'documentation' directory instead of a
'supplementary-data' one, actual supplementary data should
move to the actual data directory, which is what it does
with this commit.

02-data/supplementary/extraction_template.yml

@@ -0,0 +1,39 @@
+author: 
+year: 
+title:
+publisher:
+uri:
+discipline:
+
+country:
+period:
+maxlength:
+targeting:
+group:
+data:
+
+design:
+method:
+sample:
+unit:
+representativeness:
+causal: # 0 correlation / 1 causal
+
+theory:
+limitations:
+observation:
+  - intervention:
+    institutional:
+    structural:
+    agency:
+    inequality:
+    type: # 0 vertical / 1 horizontal
+    indicator: # 0 absolute / 1 relative
+    measures:
+    findings:
+    channels:
+    direction:
+    significance: # 0 nsg / 1 msg / 2 sg
+
+notes:
+annotation:

02-data/supplementary/un-deduplicated-study-counts.tsv

@@ -0,0 +1,10 @@
+wos_combined	1643
+Finlay2021	108
+Kumari2018	61
+Lindsay2018a	72
+Nevala2015	54
+Perez2022	131
+Pinto2021	83
+Sarker2023	151
+Schaap2018	53
+Zeinali2021	40