[js][hotfix][1.12] Fix Node EOL by bumping to 20.x (#3722)

Author: RyanSkraba

BUILD.md

@@ -10,7 +10,7 @@ The following packages must be installed before Avro can be built:
  - C: gcc, cmake, asciidoc, source-highlight, Jansson, pkg-config
  - C++: cmake 3.7.2 or greater, g++, flex, bison, libboost-dev
  - C#: .NET Core 2.2 SDK
- - JavaScript: Node 12.x+, nodejs, npm
+ - JavaScript: Node 20.x+, nodejs, npm
  - Ruby: Ruby 2.7 or greater, ruby-dev, gem, bundler, snappy
  - Perl: Perl 5.24.1 or greater, gmake, Module::Install,
    Module::Install::ReadmeFromPod, Module::Install::Repository,

share/docker/Dockerfile

@@ -122,11 +122,7 @@ RUN set -eux; \
 ENV PATH="/opt/maven/bin:${PATH}"
 
 # Install nodejs
-# The node deprecation warnings cause a 20 second sleep.
-# But mom, I'm not even tired!
-RUN curl -sSL https://deb.nodesource.com/setup_14.x \
-  | sed 's/sleep/echo "But mom!"/' \
-  | bash \
+RUN curl -sSL https://deb.nodesource.com/setup_20.x | bash \
  && apt-get -qqy install nodejs \
  && apt-get -qqy clean \
  && npm install -g grunt-cli \