chore(deps): Bump github.com/google/cel-go from 0.20.1 to 0.21.0

[dependabot]

Bumps github.com/google/cel-go from 0.20.1 to 0.21.0.

Release notes

Sourced from github.com/google/cel-go's releases.

Release v0.21.0

Features

• Math extensions update to include bitwise ops and floating point helpers #923
• Better support custom types with custom type registries #931
• repl: implement %parse #933
• Fixed partial variables extended bug and split PartialVarsEnvExtended test into two #955
• Added partial evaluations example #959
• Enable conformance tests for extensions #930
• Update cel-spec and enable optional_type conformance tests #919
• Improve token representation in AST #932
• Add function accessor to Env #978

CEL Policy Compiler

Policies which use CEL often evolve to express complex logic using multiple statements and decision criteria. The CEL Policy Compiler provides an extensible format for parsing, compiling, and composing expression graphs. Below is a simple example which can easily be compiled to a single CEL expression.

name: "my-policy"
rule:
  variables:
    - name: greeting
      expression: "'%s, %s!'"
    - name: people
      expression: >
       ['Tristan', 'Calla', 'Antoine', 'Jonathan', 'Sokwhan', 'Rebecca']
  match:
    - condition: "request.user in variables.people"
      output: "variables.greeting.format(['hello', request.user])"
    - output: "variables.greeting.format(['goodbye', 'stranger'])"

• Simple Policy Compiler #924
• Introduce protobuf message testing to policies #961
• Generate policy explanations during compilation #977
• Variable and nested rule limits #989
• Improved support for nested rules #991]

Fixes

• Delete dangling source info from macro expansion #934
• Do not re-use ID twice in exists_one macro #935
• Avoid iterating over the source multiple times during parse #936
• Fix for working with byte arrays by #958
• Stabilize macro id generation during optimization #962
• String formatting panic fix for non-literal format strings #987
• Add nil checking for wrapperspb's types #960

... (truncated)

Commits

• 3545aac Improved support for nested rules (#991)
• 5bcdb8b Check for output type agreement during the compile phase (#992)
• 1f51886 Use bytes interface value for zero native type struct fields instead of dynam...
• c9164bc Variable and nested rule limits (#989)
• 5cbef66 Prevent self-append for Issues (#988)
• 25457de Add nil checking for wrapperspb's types (#960)
• badfce0 Fix panic in formatting string for non-literal formats (#987)
• 9e64eb7 Decompose the compile and compose methods (#986)
• 37d5b96 Add a function to return a policy whose output is the explanation. (#977)
• bc96f3b Fix math.bitShiftRight for negative int (#983)
• Additional commits viewable in compare view

Dependabot will resolve any conflicts with this PR as long as you don't alter it yourself. You can also trigger a rebase manually by commenting @dependabot rebase.

---

Dependabot commands and options

You can trigger Dependabot actions by commenting on this PR:

• @dependabot rebase will rebase this PR
• @dependabot recreate will recreate this PR, overwriting any edits that have been made to it
• @dependabot merge will merge this PR after your CI passes on it
• @dependabot squash and merge will squash and merge this PR after your CI passes on it
• @dependabot cancel merge will cancel a previously requested merge and block automerging
• @dependabot reopen will reopen this PR if it is closed
• @dependabot close will close this PR and stop Dependabot recreating it. You can achieve the same result by closing it manually
• @dependabot show <dependency name> ignore conditions will show all of the ignore conditions of the specified dependency
• @dependabot ignore this major version will close this PR and stop Dependabot creating any more for this major version (unless you reopen the PR or upgrade to it yourself)
• @dependabot ignore this minor version will close this PR and stop Dependabot creating any more for this minor version (unless you reopen the PR or upgrade to it yourself)
• @dependabot ignore this dependency will close this PR and stop Dependabot creating any more for this dependency (unless you reopen the PR or upgrade to it yourself)

[dependabot]

OK, I won't notify you again about this release, but will get in touch when a new version is available. If you'd rather skip all updates until the next major or minor version, let me know by commenting @dependabot ignore this major version or @dependabot ignore this minor version. You can also ignore all major, minor, or patch releases for a dependency by adding an ignore condition with the desired update_types to your config file.

If you change your mind, just re-open this PR and I'll resolve any conflicts on it.