VSCode extension AST viewer tab not showing AST for some files.

**Description of the issue**

Hello,
I am using the codeql using VSCode extension. I want to generate AST for a particular file but it just won't show me the AST.
Please note that I can view the AST for some files(majority of them) but for a few files I am unable to do so.
All these files are present in the CodeQL Database that was generated. I have verified from the src.zip file.
There is no error when I click on `CODEQL: View AST` button on right click in my src file in both working and non-working cases.(I've added logs at the end of this issue)
I have attached Images for the extension tab when It generates an AST and when it doesn't.

**Logs for `CodeQL: View AST` working case:**
```
Reading bqrs data using CodeQL CLI: bqrs decode -v --log-to-stderr --format json --entities=id,url,string --result-set nodes /var/folders/p9/gkqn3kwx2llcc6m40ky4x25c0000gn/T/queries_-97292-WeHCoy2Wtomq/contextual-query-storage/printAst.ql-nFz0NKDOSDiYpdH5Ads_w/results.bqrs...

CLI command succeeded.
Reading bqrs data using CodeQL CLI: bqrs decode -v --log-to-stderr --format json --entities=id,url,string --result-set edges /var/folders/p9/gkqn3kwx2llcc6m40ky4x25c0000gn/T/queries_-97292-WeHCoy2Wtomq/contextual-query-storage/printAst.ql-nFz0NKDOSDiYpdH5Ads_w/results.bqrs...

CLI command succeeded.
Reading bqrs data using CodeQL CLI: bqrs decode -v --log-to-stderr --format json --entities=id,url,string --result-set graphProperties /var/folders/p9/gkqn3kwx2llcc6m40ky4x25c0000gn/T/queries_-97292-WeHCoy2Wtomq/contextual-query-storage/printAst.ql-nFz0NKDOSDiYpdH5Ads_w/results.bqrs...

CLI command succeeded.

```

**Logs for `CodeQL: View AST` non-working case:**

```
Reading bqrs data using CodeQL CLI: bqrs decode -v --log-to-stderr --format json --entities=id,url,string --result-set nodes /var/folders/p9/gkqn3kwx2llcc6m40ky4x25c0000gn/T/queries_-97292-WeHCoy2Wtomq/contextual-query-storage/printAst.ql-yst2iLGzGqpy1dQl2oDU4/results.bqrs...

CLI command succeeded.
Reading bqrs data using CodeQL CLI: bqrs decode -v --log-to-stderr --format json --entities=id,url,string --result-set edges /var/folders/p9/gkqn3kwx2llcc6m40ky4x25c0000gn/T/queries_-97292-WeHCoy2Wtomq/contextual-query-storage/printAst.ql-yst2iLGzGqpy1dQl2oDU4/results.bqrs...

CLI command succeeded.
Reading bqrs data using CodeQL CLI: bqrs decode -v --log-to-stderr --format json --entities=id,url,string --result-set graphProperties /var/folders/p9/gkqn3kwx2llcc6m40ky4x25c0000gn/T/queries_-97292-WeHCoy2Wtomq/contextual-query-storage/printAst.ql-yst2iLGzGqpy1dQl2oDU4/results.bqrs...

CLI command succeeded.
```