json: add schema validation benchmarks

Include a Citi-Bike derived dataset, and a (non-working) GitHub dataset.

The GitHub benchmark is currently non-functional because it violates the
maximum size of our schema intern table.

Baseline (on my machine):

rides1x                 time:   [43.090 ms 43.128 ms 43.165 ms]
                        change: [+0.2674% +0.3935% +0.5320%] (p = 0.00 < 0.05)
                        Change within noise threshold.
Found 6 outliers among 100 measurements (6.00%)
  4 (4.00%) low mild
  2 (2.00%) high mild

rides4x                 time:   [245.73 ms 245.82 ms 245.92 ms]
                        change: [-0.4382% -0.3816% -0.3286%] (p = 0.00 < 0.05)
                        Change within noise threshold.
Found 2 outliers among 100 measurements (2.00%)
  2 (2.00%) high mild

Issue estuary#226

Author: jgraettinger

.gitattributes

@@ -0,0 +1,5 @@
+crates/json/benches/testdata/citi-rides1.json filter=lfs diff=lfs merge=lfs -text
+crates/json/benches/testdata/github-scrape1.json filter=lfs diff=lfs merge=lfs -text
+crates/json/benches/testdata/github-scrape2.json filter=lfs diff=lfs merge=lfs -text
+crates/json/benches/testdata/github-scrape3.json filter=lfs diff=lfs merge=lfs -text
+crates/json/benches/testdata/github-scrape4.json filter=lfs diff=lfs merge=lfs -text