Fix: fixed frontend build error

[TonySD]

pnpm updated to version 9, and this, supposedly ruins the build:

 => ERROR [front front-build 2/3] RUN --mount=type=cache,id=pnpm,target=/pnpm/store pnpm install --frozen-lockfile                                                                        0.9s
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 > [front front-build 2/3] RUN --mount=type=cache,id=pnpm,target=/pnpm/store pnpm install --frozen-lockfile:
0.689 /usr/local/lib/node_modules/corepack/dist/lib/corepack.cjs:21535
0.689   if (key == null || signature == null) throw new Error(`Cannot find matching keyid: ${JSON.stringify({ signatures, keys })}`);
0.689                                               ^
0.689
0.689 Error: Cannot find matching keyid: {"signatures":[{"sig":"MEUCIQC8OzFLCoQAQwmVP0rCi9pnLihViK6ifO20e6CQu337BwIgfhzo2SVsCmifbOuvXg1+3CIPBeKfrV5ibPWFI/NdBOo=","keyid":"SHA256:DhQ8wR5APBvFHLF/+Tc+AYvPOdTpcIDqOhxsBHRwC7U"}],"keys":[{"expires":null,"keyid":"SHA256:jl3bwswu80PjjokCgh0o2w5c2U4LhQAE57gj9cz1kzA","keytype":"ecdsa-sha2-nistp256","scheme":"ecdsa-sha2-nistp256","key":"MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAE1Olb3zMAFFxXKHiIkQO5cJ3Yhl5i6UPp+IhuteBJbuHcA5UogKo0EWtlWwW6KSaKoTNEYL7JlCQiVnkhBktUgg=="}]}
0.689     at verifySignature (/usr/local/lib/node_modules/corepack/dist/lib/corepack.cjs:21535:47)
0.689     at fetchLatestStableVersion (/usr/local/lib/node_modules/corepack/dist/lib/corepack.cjs:21553:5)
0.689     at process.processTicksAndRejections (node:internal/process/task_queues:95:5)
0.689     at async fetchLatestStableVersion2 (/usr/local/lib/node_modules/corepack/dist/lib/corepack.cjs:21672:14)
0.689     at async Engine.getDefaultVersion (/usr/local/lib/node_modules/corepack/dist/lib/corepack.cjs:22298:23)
0.689     at async Engine.executePackageManagerRequest (/usr/local/lib/node_modules/corepack/dist/lib/corepack.cjs:22396:47)
0.689     at async Object.runMain (/usr/local/lib/node_modules/corepack/dist/lib/corepack.cjs:23102:5)
0.689
0.689 Node.js v20.18.3
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failed to solve: process "/bin/sh -c pnpm install --frozen-lockfile" did not complete successfully: exit code: 1