bump .eslintrc.json ecmaVersion to 2021

[simon-id]

What does this PR do?

Change the ecmaVersion value for ESLint from 2020 to 2021.

Motivation

We dropped node 14 and I want to use ??= and this is the min version it works.

[github-actions]

Overall package size

Self size: 6.53 MB
Deduped: 61.79 MB
No deduping: 62.07 MB

Dependency sizes

name	version	self size	total size
@datadog/native-appsec	8.0.1	15.59 MB	15.6 MB
@datadog/native-iast-taint-tracking	2.1.0	14.91 MB	14.92 MB
@datadog/pprof	5.3.0	9.85 MB	10.22 MB
protobufjs	7.2.5	2.77 MB	6.56 MB
@datadog/native-iast-rewriter	2.3.1	2.15 MB	2.24 MB
@opentelemetry/core	1.14.0	872.87 kB	1.47 MB
@datadog/native-metrics	2.0.0	898.77 kB	1.3 MB
@opentelemetry/api	1.8.0	1.21 MB	1.21 MB
import-in-the-middle	1.7.4	70.19 kB	739.86 kB
msgpack-lite	0.1.26	201.16 kB	281.59 kB
opentracing	0.14.7	194.81 kB	194.81 kB
semver	7.5.4	93.4 kB	123.8 kB
pprof-format	2.1.0	111.69 kB	111.69 kB
@datadog/sketches-js	2.1.0	109.9 kB	109.9 kB
lodash.sortby	4.7.0	75.76 kB	75.76 kB
lru-cache	7.14.0	74.95 kB	74.95 kB
ignore	5.2.4	51.22 kB	51.22 kB
int64-buffer	0.1.10	49.18 kB	49.18 kB
shell-quote	1.8.1	44.96 kB	44.96 kB
istanbul-lib-coverage	3.2.0	29.34 kB	29.34 kB
tlhunter-sorted-set	0.1.0	24.94 kB	24.94 kB
limiter	1.1.5	23.17 kB	23.17 kB
dc-polyfill	0.1.4	23.1 kB	23.1 kB
retry	0.13.1	18.85 kB	18.85 kB
jest-docblock	29.7.0	8.99 kB	12.76 kB
crypto-randomuuid	1.0.0	11.18 kB	11.18 kB
path-to-regexp	0.1.7	6.78 kB	6.78 kB
koalas	1.0.2	6.47 kB	6.47 kB
module-details-from-path	1.0.3	4.47 kB	4.47 kB

_{🤖 This report was automatically generated by heaviest-objects-in-the-universe}

[pr-commenter]

Benchmarks

Benchmark execution time: 2024-05-29 07:01:05

Comparing candidate commit dbd1947 in PR branch ecma_version_2021 with baseline commit cf8964f in branch master.

Found 1 performance improvements and 0 performance regressions! Performance is the same for 261 metrics, 4 unstable metrics.

scenario:plugin-graphql-with-depth-and-collapse-on-18

• 🟩 max_rss_usage [-153.799MB; -103.301MB] or [-15.969%; -10.726%]