chore(ci): add node 18 & 20 to ci targets

[piotr-roslaniec]

Type of PR:

• Other

Required reviews:

• 1

What this does:

• Adds Node 18 & 20 as CI targets
• Ensure support for these Node versions
• Communicate deprecation of support for Node 16

Issues fixed/closed:

• Fixes #...

Why it's needed:

Explain how this PR fits in the greater context of the NuCypher Network.
E.g., if this PR address a nucypher/productdev issue, let reviewers know!

Notes for reviewers:

What should reviewers focus on?
Is there a particular commit/function/section of your PR that requires more attention from reviewers?

[codecov-commenter]

Codecov Report

Merging #284 (cb3c120) into update-deps (f183d9e) will not change coverage.
The diff coverage is n/a.

@@             Coverage Diff              @@
##           update-deps     #284   +/-   ##
============================================
  Coverage        80.56%   80.56%           
============================================
  Files               36       36           
  Lines              983      983           
  Branches           108      108           
============================================
  Hits               792      792           
  Misses             183      183           
  Partials             8        8           

[github-actions]

Bundled size for the package is listed below:

build/main/src/characters: 74.22 KB
build/main/src/kits: 19.53 KB
build/main/src/conditions/context: 42.97 KB
build/main/src/conditions/predefined: 19.53 KB
build/main/src/conditions/base: 54.69 KB
build/main/src/conditions: 156.25 KB
build/main/src/agents: 39.06 KB
build/main/src/sdk/strategy: 35.16 KB
build/main/src/sdk: 46.88 KB
build/main/src/policies: 19.53 KB
build/main/src: 433.59 KB
build/main/types/ethers-contracts/factories: 113.28 KB
build/main/types/ethers-contracts: 183.59 KB
build/main/types: 187.50 KB
build/main: 679.69 KB
build/module/src/characters: 74.22 KB
build/module/src/kits: 19.53 KB
build/module/src/conditions/context: 42.97 KB
build/module/src/conditions/predefined: 19.53 KB
build/module/src/conditions/base: 54.69 KB
build/module/src/conditions: 156.25 KB
build/module/src/agents: 39.06 KB
build/module/src/sdk/strategy: 31.25 KB
build/module/src/sdk: 42.97 KB
build/module/src/policies: 19.53 KB
build/module/src: 425.78 KB
build/module/types/ethers-contracts/factories: 113.28 KB
build/module/types/ethers-contracts: 183.59 KB
build/module/types: 187.50 KB
build/module: 671.88 KB
build: 1.32 MB

[piotr-roslaniec]

Superseded by #299