fix blockly version to avoid deprecation

[Syuparn]

This PR fixes the blockly version to fix errors that occur when moving blocks.

Currently, when using containers built by Dockerfile, blocks cannot be selected and an error below is raised.

 Uncaught Error: sCASP generator does not know how to generate code for block type "unattributed_fact".
     at Object.blockToCode (generator.ts:259:13)
     at Object.workspaceToCode (generator.ts:159:23)
     at liveCode (blawx2scasp.js:3:20)
     at WorkspaceSvg$$module$build$src$core$workspace_svg.fireChangeListener (workspace.ts:704:7)
     at fireNow$$module$build$src$core$events$utils (utils.ts:131:49)

This is because installed blockly version is too new to run the block generator functions used in Blawx.

This PR fixes the installed blockly version to use the same version as the current tag of the official Docker image lexpedite/blawx:latest.