`lastIndexOf` in `sourcemap-register.js` causes Github to flag `Incorrect suffix check`

I think this `sourcemap-register.js` file is an output of this module:
https://raw.githubusercontent.com/gradle/gradle-build-action/aeb3e0fcd750be80d74f07ee94363abdf2b51020/dist/post/sourcemap-register.js

which contains this:
```js
var n=0;while(r.indexOf(e+"/")!==0){var t=e.lastIndexOf("/");
if(t<0){return r}e=e.slice(0,t);if(e.match(/^([^\/]+:\/)?\/*$/)){return r}++n}return Array(n+1).join("../")+r.substr(e.length+1)}r.relative=relative;var o=function(){var e=Object.create(null);return!("__proto__"in e)}();function identity(e){return e}function toSetString(e){if(isProtoString(e)){return"$"+e}return e}r.toSetString=o?identity:toSetString;function fromSetString(e){if(isProtoString(e)){return e.slice(1)}return e}r.fromSetString=o?identity:fromSetString;function isProtoString(e){if(!e){return false}var r=e.length;if(r<9){return false}if(e.charCodeAt(r-1)!==95||e.charCodeAt(r-2)!==95||e.charCodeAt(r-3)!==111||e.charCodeAt(r-4)!==116||e.charCodeAt(r-5)!==111||e.charCodeAt(r-6)!==114||e.charCodeAt(r-7)!==112||e.charCodeAt(r-8)!==95||e.charCodeAt(r-9)!==95){return false}for(var n=r-10;n>=0;n--){if(e.charCodeAt(n)!==36){return false}}return true}function compareByOriginalPositions(e,r,n){var t=strcmp(e.source,r.source);if(t!==0){return t}t=e.originalLine-r.originalLine;if(t!==0){return t}t=e.originalColumn-r.originalColumn;if(t!==0||n){return t}t=e.generatedColumn-r.generatedColumn;if(t!==0){return t}t=e.generatedLine-r.generatedLine;if(t!==0){return t}return strcmp(e.name,r.name)}r.compareByOriginalPositions=compareByOriginalPositions;function compareByGeneratedPositionsDeflated(e,r,n){var t=e.generatedLine-r.generatedLine;if(t!==0){return t}t=e.generatedColumn-r.generatedColumn;if(t!==0||n){return t}t=strcmp(e.source,r.source);if(t!==0){return t}t=e.originalLine-r.originalLine;if(t!==0){return t}t=e.originalColumn-r.originalColumn;if(t!==0){return t}return strcmp(e.name,r.name)}r.compareByGeneratedPositionsDeflated=compareByGeneratedPositionsDeflated;function strcmp(e,r){if(e===r){return 0}if(e===null){return 1}if(r===null){return-1}if(e>r){return 1}return-1}function compareByGeneratedPositionsInflated(e,r){var n=e.generatedLine-r.generatedLine;if(n!==0){return n}n=e.generatedColumn-r.generatedColumn;if(n!==0){return n}n=strcmp(e.source,r.source);if(n!==0){return n}n=e.originalLine-r.originalLine;if(n!==0){return n}n=e.originalColumn-r.originalColumn;if(n!==0){return n}return strcmp(e.name,r.name)}r.compareByGeneratedPositionsInflated=compareByGeneratedPositionsInflated;function parseSourceMapInput(e){return JSON.parse(e.replace(/^\)]}'[^\n]*\n/,""))}r.parseSourceMapInput=parseSourceMapInput;function computeSourceURL(e,r,n){r=r||"";if(e){if(e[e.length-1]!=="/"&&r[0]!=="/"){e+="/"}r=e+r}if(n){var t=urlParse(n);
if(!t){throw new Error("sourceMapURL could not be parsed")}if(t.path){var o=t.path.lastIndexOf("/");
```

Which causes Github advanced security to issue this "high" severity error:

https://codeql.github.com/codeql-query-help/javascript/js-incorrect-suffix-check/

Would be great if you can confirm if this is related to [node-source-map-support](https://github.com/evanw/node-source-map-support)

If it is related, can you add the suggested fix here: https://codeql.github.com/codeql-query-help/javascript/js-incorrect-suffix-check/
to avoid the error from GH advanced security. :)

まず、報告された dist/post/sourcemap-register.js の出力をソースまでたどり、それが node-source-map-support に由来するか確認します。CodeQL の incorrect-suffix-check に関するガイダンスを確認し、適切なソース変更を判断します。生成されたファイルが報告された警告を発生させなくなり、プロジェクトの関連するチェックに合格すれば完了です。

索引モデルが issue の本文から書いたものです。