fix(core): support no-op rewrites

[dphang]

Fixes: #1328

[slsnextbot]

Handler Size Report

There are changes to handler sizes. Please review.

Base Handler Sizes (kB) (commit df2b703)

{
    "Lambda@Edge": {
        "Default Lambda": {
            "Standard": 1231,
            "Minified": 435
        },
        "API Lambda": {
            "Standard": 81,
            "Minified": 33
        },
        "Image Lambda": {
            "Standard": 903,
            "Minified": 357
        },
        "Regeneration Lambda": {
            "Standard": 629,
            "Minified": 223
        }
    }
}

New Handler Sizes (kB) (commit 56a7ebd)

{
    "Lambda@Edge": {
        "Default Lambda": {
            "Standard": 1231,
            "Minified": 435
        },
        "API Lambda": {
            "Standard": 85,
            "Minified": 34
        },
        "Image Lambda": {
            "Standard": 903,
            "Minified": 357
        },
        "Regeneration Lambda": {
            "Standard": 629,
            "Minified": 223
        }
    }
}

[codecov]

Codecov Report

Merging #1329 (56a7ebd) into master (df2b703) will increase coverage by 0.01%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master    #1329      +/-   ##
==========================================
+ Coverage   83.61%   83.63%   +0.01%     
==========================================
  Files          97       97              
  Lines        3345     3349       +4     
  Branches     1001     1003       +2     
==========================================
+ Hits         2797     2801       +4     
  Misses        486      486              
  Partials       62       62              

Impacted Files	Coverage Δ
packages/libs/core/src/route/page.ts	100.00% <100.00%> (ø)
packages/libs/core/src/route/rewrite.ts	100.00% <100.00%> (ø)

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[dphang]

CF distributions seem to be stuck in progress - seems to be AWS issue. Will retry later.

[dphang]

e2e passed for most part (failed on external API rewrite due to GH api limits - we could probably try to move to another to avoid this)