Move /build/ dev dependencies to root

[alexdima]

For #112718

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size saving: 1.22%
file count saving: 10.03%
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PATH                                             BYTES      FILES
root                                       811,962,081     38,963
remote                                     172,606,391      1,759
build                                       75,652,346      1,836
extensions/typescript-language-features     64,892,021        735
test/smoke                                  63,022,613      5,024
test/automation                             60,712,649      4,728
test/integration/browser                    53,567,321        484
extensions                                  30,564,829         84
extensions/html-language-features/server     6,260,414        414
extensions/emmet                             6,230,887        438
remote/web                                   5,728,559        267
extensions/css-language-features/server      4,824,505        338
extensions/markdown-language-features        4,697,992      1,136
extensions/git                               4,542,196        405
extensions/microsoft-authentication          4,445,327        662
extensions/github                            4,186,258        399
extensions/json-language-features            3,492,388        682
extensions/json-language-features/server     2,921,100        418
extensions/html-language-features            2,860,474        563
extensions/github-authentication             2,790,450        466
extensions/npm                               2,564,903        399
extensions/extension-editing                 2,218,244        249
extensions/css-language-features             2,151,031        335
build/lib/watch                              1,249,570        512
extensions/image-preview                       881,680        235
extensions/configuration-editing               846,610         72
extensions/vscode-colorize-tests               821,302         66
extensions/vscode-custom-editor-tests          719,021         71
extensions/vscode-notebook-tests               696,288         54
extensions/debug-auto-launch                   678,927         56
extensions/debug-server-ready                  678,927         56
extensions/grunt                               678,927         56
extensions/gulp                                678,927         56
extensions/jake                                678,927         56
extensions/merge-conflict                      678,927         56
extensions/php-language-features               678,927         56
extensions/vscode-api-tests                    666,633         54
extensions/git-ui                              654,993         50
extensions/vscode-test-resolver                654,993         50
TOTAL                                    1,404,838,558     62,340